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question:Olly wants to get shoes to protect his pets' paws. He owns 3 dogs, some cats, and a ferret. He needs 24 shoes in total. How many cats does he own?
answer:First, I need to determine how many shoes each type of pet requires. Assuming each animal needs 4 shoes, one for each paw.Olly has 3 dogs, so for the dogs, he needs 3 dogs multiplied by 4 shoes per dog, which equals 12 shoes.He also has a ferret, which would need 4 shoes.Adding the shoes for the dogs and the ferret together, Olly needs 12 shoes for the dogs plus 4 shoes for the ferret, totaling 16 shoes.Olly needs 24 shoes in total, so the number of shoes needed for the cats is 24 shoes (total) minus 16 shoes (for dogs and ferret), which equals 8 shoes.Since each cat needs 4 shoes, the number of cats Olly owns is 8 shoes divided by 4 shoes per cat, resulting in 2 cats.
question:Given a regular pentagon (ABCDE), point (K) is marked on side (AE) and point (L) is marked on side (CD). It is known that (angle LAE + angle KCD = 108^circ) and the ratio (AK: KE = 3:7). Find (CL: AB).(Note: A regular pentagon is a pentagon in which all sides and angles are equal.)
answer:Alright, so I have this problem about a regular pentagon (ABCDE). Points (K) and (L) are marked on sides (AE) and (CD) respectively. I know that the sum of angles (angle LAE + angle KCD = 108^circ), and the ratio (AK:KE = 3:7). I need to find the ratio (CL:AB).First, I remember that in a regular pentagon, all sides are equal and all internal angles are equal. Each internal angle in a regular pentagon is (108^circ). That might be useful.Given (AK:KE = 3:7), I can denote (AK = 3x) and (KE = 7x), so the entire side (AE = AK + KE = 10x). Since all sides of the pentagon are equal, (AB = BC = CD = DE = EA = 10x).Now, the problem mentions angles (angle LAE) and (angle KCD) adding up to (108^circ). Let me denote (angle LAE = alpha), so (angle KCD = 108^circ - alpha).I think drawing a diagram might help visualize the problem. Let me sketch a regular pentagon (ABCDE), label points (K) on (AE) and (L) on (CD). Then, I can mark the angles (alpha) at (A) and (108^circ - alpha) at (C).Since (ABCDE) is regular, all sides are equal, and all central angles are equal. The central angle for a regular pentagon is (72^circ) because (360^circ / 5 = 72^circ). Maybe that's useful for some triangle properties.Looking at triangle (AEL), I know (AE = 10x), and (AK = 3x). If I can find some relationships in triangles involving (L) and (K), maybe I can find the lengths needed.Wait, maybe I can use the Law of Sines or Cosines in some triangles here. Let's see.In triangle (AEL), if I can find some angles, I might relate the sides. But I only know one angle, (angle LAE = alpha). Maybe I need more information.Alternatively, since the sum of (angle LAE) and (angle KCD) is (108^circ), and each internal angle of the pentagon is (108^circ), perhaps there's a way to relate these angles through the pentagon's properties.I recall that in a regular pentagon, the diagonals intersect at the golden ratio. The ratio of the diagonal to the side is the golden ratio (phi = frac{1+sqrt{5}}{2} approx 1.618). Maybe that's relevant here.But I'm not sure yet. Let me think about the triangles formed by points (K) and (L).Looking at triangle (AKC), I know (AK = 3x) and (AC) is a diagonal of the pentagon. Since (AC = phi times AB), and (AB = 10x), then (AC = 10x times phi).Wait, but I don't know if triangle (AKC) is a triangle I can work with. Maybe I should look at triangle (CKL) or something else.Alternatively, maybe I can use similar triangles. If I can find two triangles that are similar, I can set up a proportion.Given that (angle LAE + angle KCD = 108^circ), and each internal angle is (108^circ), perhaps the lines (AL) and (CK) intersect at some point inside the pentagon, forming triangles with known angles.Wait, maybe I can use the fact that the sum of those two angles is equal to the internal angle of the pentagon. That might imply that lines (AL) and (CK) are related in some way, maybe forming another angle that's supplementary or something.Alternatively, maybe I can use coordinate geometry. Assign coordinates to the pentagon's vertices and then find the coordinates of (K) and (L), then compute the lengths.Let me try that approach. Let's place the pentagon in a coordinate system. Let me assume point (A) is at ((0,0)), and the pentagon is centered at the origin. But actually, regular pentagons are often placed with one vertex at the top, but for simplicity, let me place point (A) at ((1,0)) on the unit circle.Wait, but scaling might complicate things. Maybe it's better to assign coordinates based on side lengths.Alternatively, use complex numbers. Each vertex can be represented as a complex number on the unit circle, spaced at (72^circ) apart.But maybe that's overcomplicating. Let me try a different approach.Since all sides are equal and all angles are (108^circ), maybe I can use the properties of isosceles triangles within the pentagon.Looking at triangle (AEL), it's an isosceles triangle with (AE = 10x) and base (EL). But I don't know much about (EL).Wait, maybe I can consider triangles (AEL) and (KCD). Since (AK:KE = 3:7), and (CD = 10x), perhaps (CL) relates to (CD) in a similar ratio.But I need to find (CL:AB), which is (CL:10x).Alternatively, maybe I can use the fact that the sum of the angles (angle LAE + angle KCD = 108^circ) implies some relationship between the triangles (AEL) and (KCD).Wait, if I consider triangles (AEL) and (KCD), maybe they are similar? If their corresponding angles are equal, then their sides would be proportional.But I only know one angle in each triangle. Maybe not enough.Alternatively, maybe the lines (AL) and (CK) intersect at some point, creating vertical angles or something.Wait, maybe I can use the Law of Sines in triangles (AEL) and (KCD).In triangle (AEL), (angle LAE = alpha), side (AE = 10x), and side (EL) opposite to (alpha). So, by the Law of Sines:[frac{EL}{sin alpha} = frac{AE}{sin angle ALE}]Similarly, in triangle (KCD), (angle KCD = 108^circ - alpha), side (CD = 10x), and side (KD) opposite to (108^circ - alpha). So:[frac{KD}{sin (108^circ - alpha)} = frac{CD}{sin angle CKD}]But I don't know (angle ALE) or (angle CKD), so maybe this isn't helpful yet.Wait, maybe I can relate these two triangles through some other property.Alternatively, since (AK:KE = 3:7), and (AE = 10x), then (AK = 3x) and (KE = 7x). Maybe I can use this ratio in some way.If I consider triangle (AKC), I know (AK = 3x) and (AC) is a diagonal. Since in a regular pentagon, the ratio of diagonal to side is (phi), so (AC = phi times AB = phi times 10x).But I don't know if triangle (AKC) is useful.Wait, maybe I can use the fact that in a regular pentagon, the diagonals intersect at the golden ratio. So, if I extend some lines, maybe I can find some proportional segments.Alternatively, maybe I can use coordinate geometry. Let me assign coordinates to the pentagon.Let me place point (A) at ((0,0)), (B) at ((1,0)), and then construct the pentagon from there. But I need to find the coordinates of all points.Wait, maybe it's better to use a unit pentagon for simplicity, where each side is length 1, and then scale accordingly.But since the ratio (AK:KE = 3:7), maybe it's better to keep the side length as (10x) to make calculations easier.Alternatively, set (x = 1), so (AK = 3), (KE = 7), and (AE = 10).Let me try that. So, side length (AB = 10), and (AK = 3), (KE = 7).Now, I need to find (CL). Since (CL) is a segment on side (CD), which has length (10), so (CL + LD = 10). If I can find (LD), I can find (CL).Alternatively, maybe I can find (CL) directly.Given that (angle LAE + angle KCD = 108^circ), and each internal angle is (108^circ), perhaps there's a way to relate these angles through the pentagon's properties.Wait, maybe I can use the fact that in a regular pentagon, the diagonals trisection the angles. So, each angle is (108^circ), and the diagonals split them into (36^circ) and (72^circ).Wait, actually, in a regular pentagon, the diagonals intersect at angles of (36^circ), (72^circ), etc.Wait, maybe I can consider the triangles formed by the diagonals.Alternatively, maybe I can use trigonometric identities.Wait, let me think about triangle (AEL). I know (AE = 10), (AK = 3), and (angle LAE = alpha). Maybe I can express (EL) in terms of (alpha).Similarly, in triangle (KCD), I know (CD = 10), (KD) is something, and (angle KCD = 108^circ - alpha).Wait, maybe I can relate these two triangles through some proportionality.Alternatively, maybe I can use the fact that the sum of the angles is (108^circ), which is the internal angle of the pentagon.Wait, perhaps lines (AL) and (CK) intersect at some point inside the pentagon, forming an angle of (108^circ). Maybe that can help.Alternatively, maybe I can use the Law of Sines in triangles (AEL) and (KCD).In triangle (AEL):[frac{EL}{sin alpha} = frac{AE}{sin angle ALE}]In triangle (KCD):[frac{KD}{sin (108^circ - alpha)} = frac{CD}{sin angle CKD}]But I don't know (angle ALE) or (angle CKD), so maybe this isn't helpful yet.Wait, maybe I can consider that the sum of angles around a point is (360^circ). If I can find some angles around point (K) or (L), maybe I can find relationships.Alternatively, maybe I can use the fact that in a regular pentagon, the diagonals form a star shape, and the intersection points divide the diagonals in the golden ratio.Wait, maybe I can use the golden ratio here. Since (AK:KE = 3:7), which is not the golden ratio, but maybe the position of (K) relates to the golden ratio in some way.Alternatively, maybe I can use coordinate geometry. Let me assign coordinates to the pentagon.Let me place point (A) at ((0,0)), and construct the pentagon such that each vertex is spaced at (72^circ). But this might get complicated.Alternatively, use vectors or complex numbers.Wait, maybe I can use complex numbers. Let me represent each vertex as a complex number on the unit circle.Let me denote the vertices as (A, B, C, D, E) corresponding to complex numbers (1, omega, omega^2, omega^3, omega^4), where (omega = e^{2pi i /5}).But this might be overcomplicating.Alternatively, maybe I can use the fact that in a regular pentagon, the length of a diagonal is (phi) times the side length.Given that, if (AB = 10), then the diagonal (AC = 10phi).But I'm not sure how that helps with points (K) and (L).Wait, maybe I can consider triangles (AEL) and (KCD) and see if they are similar.In triangle (AEL), sides are (AE = 10), (AK = 3), and angle (alpha).In triangle (KCD), sides are (CD = 10), (KD = ?), and angle (108^circ - alpha).If these triangles are similar, then the ratios of their sides would be equal.But I don't know if they are similar.Alternatively, maybe I can use the fact that the sum of the angles is (108^circ), which is the internal angle, so maybe the lines (AL) and (CK) form some relationship.Wait, maybe I can use the Law of Cosines in triangles (AEL) and (KCD).In triangle (AEL):[EL^2 = AE^2 + AL^2 - 2 times AE times AL times cos alpha]In triangle (KCD):[KD^2 = CD^2 + CK^2 - 2 times CD times CK times cos (108^circ - alpha)]But I don't know (AL) or (CK), so this might not help.Wait, maybe I can consider the areas of these triangles.Alternatively, maybe I can use the fact that the sum of the angles is (108^circ) to relate the sides.Wait, perhaps I can use the Law of Sines in both triangles and set up a proportion.In triangle (AEL):[frac{EL}{sin alpha} = frac{AE}{sin angle ALE}]In triangle (KCD):[frac{KD}{sin (108^circ - alpha)} = frac{CD}{sin angle CKD}]But without knowing the other angles, this is difficult.Wait, maybe I can consider that the sum of angles around point (K) is (360^circ). So, at point (K), the angles around it would be (angle AKC), (angle CKD), and others.But I'm not sure.Wait, maybe I can use the fact that in a regular pentagon, the diagonals intersect at angles of (36^circ), so maybe some of these angles are related.Alternatively, maybe I can use the fact that the diagonals divide the angles into (36^circ) and (72^circ).Wait, if I consider the diagonal from (A) to (C), it splits the angle at (A) into two angles of (36^circ) and (72^circ). Similarly, the diagonal from (C) to (E) splits the angle at (C) into (36^circ) and (72^circ).Given that, maybe (angle LAE) is related to these splits.Wait, if (angle LAE = alpha), and the diagonal splits the angle into (36^circ) and (72^circ), maybe (alpha) is either (36^circ) or (72^circ), but since (alpha + (108^circ - alpha) = 108^circ), which is the internal angle, maybe (alpha) is (36^circ) and (108^circ - alpha = 72^circ), or vice versa.Wait, let's test that. If (alpha = 36^circ), then (angle KCD = 72^circ). If (alpha = 72^circ), then (angle KCD = 36^circ).But I don't know which one it is. Maybe both cases are possible, but perhaps the ratio (AK:KE = 3:7) will determine which one it is.Wait, if (alpha = 36^circ), then in triangle (AEL), side (EL) would be shorter, whereas if (alpha = 72^circ), (EL) would be longer.But I'm not sure.Alternatively, maybe I can use the fact that in a regular pentagon, the ratio of the diagonal to the side is (phi), so (AC = phi times AB).Given that, if (AB = 10), then (AC = 10phi).But how does that help with points (K) and (L)?Wait, maybe I can consider triangle (AKC). I know (AK = 3), (AC = 10phi), and angle at (A) is (108^circ). Maybe I can use the Law of Cosines to find (KC).Wait, in triangle (AKC), sides (AK = 3), (AC = 10phi), and angle at (A) is (108^circ). So, by the Law of Cosines:[KC^2 = AK^2 + AC^2 - 2 times AK times AC times cos 108^circ]But this seems complicated, and I don't know if it's necessary.Alternatively, maybe I can use the fact that in triangle (AKC), the ratio of sides is related to the angles.Wait, maybe I can use the Law of Sines:[frac{KC}{sin angle KAC} = frac{AK}{sin angle ACK}]But I don't know the angles.Wait, maybe I can consider that (angle KAC) is related to (alpha). Since (angle LAE = alpha), and (K) is on (AE), maybe (angle KAC = alpha) or something.Wait, no, because (K) is on (AE), so (angle KAC) would be the same as (angle KAE), which is (alpha). So, (angle KAC = alpha).Similarly, in triangle (KCD), (angle KCD = 108^circ - alpha).Wait, maybe I can relate triangles (AKC) and (KCD).In triangle (AKC):[frac{KC}{sin alpha} = frac{AK}{sin angle ACK}]In triangle (KCD):[frac{KD}{sin (108^circ - alpha)} = frac{CD}{sin angle CKD}]But I don't know (angle ACK) or (angle CKD).Wait, maybe I can consider that (angle ACK) and (angle CKD) are related through the pentagon's properties.Alternatively, maybe I can use the fact that the sum of angles around point (C) is (360^circ). So, (angle KCD + angle DCE + angle ECA + angle ACK = 360^circ). But I'm not sure.Wait, maybe I can consider that in the regular pentagon, the diagonals intersect at angles of (36^circ), so maybe (angle ACK = 36^circ) or something.Alternatively, maybe I can use the fact that in a regular pentagon, the central angles are (72^circ), so the angles subtended by the sides at the center are (72^circ).Wait, maybe I can use the fact that the central angles are (72^circ), so the arcs between the vertices are (72^circ). Maybe that can help with some trigonometric calculations.Alternatively, maybe I can use the fact that in a regular pentagon, the distance from a vertex to the center is the same for all vertices, and that can be used to find some lengths.Wait, maybe I can use coordinate geometry after all. Let me assign coordinates to the pentagon.Let me place the pentagon in a coordinate system with center at the origin. Let me assume the pentagon is regular and centered at the origin with radius (R). Then, the coordinates of the vertices can be given by:[A: (R, 0)][B: (R cos 72^circ, R sin 72^circ)][C: (R cos 144^circ, R sin 144^circ)][D: (R cos 216^circ, R sin 216^circ)][E: (R cos 288^circ, R sin 288^circ)]But this might be complicated, but let's try.Given that, I can find the coordinates of points (A, B, C, D, E). Then, I can find the coordinates of (K) on (AE) and (L) on (CD).Given (AK:KE = 3:7), so (K) divides (AE) in the ratio (3:7). So, using the section formula, the coordinates of (K) can be found.Similarly, (L) is on (CD), but I don't know the ratio yet. But I know that (angle LAE + angle KCD = 108^circ). Maybe I can express these angles in terms of coordinates and solve for the ratio.This seems promising, but it's going to be calculation-heavy.Let me proceed step by step.First, let me set the radius (R = 1) for simplicity. Then, the coordinates are:[A: (1, 0)][B: (cos 72^circ, sin 72^circ) approx (0.3090, 0.9511)][C: (cos 144^circ, sin 144^circ) approx (-0.8090, 0.5878)][D: (cos 216^circ, sin 216^circ) approx (-0.8090, -0.5878)][E: (cos 288^circ, sin 288^circ) approx (0.3090, -0.9511)]Now, point (K) is on (AE) such that (AK:KE = 3:7). Since (A) is at ((1,0)) and (E) is at ((0.3090, -0.9511)), the coordinates of (K) can be found using the section formula.The section formula for a point dividing a line segment in the ratio (m:n) is:[left( frac{m x_2 + n x_1}{m + n}, frac{m y_2 + n y_1}{m + n} right)]Here, (m = 3), (n = 7), (A = (1,0)), (E = (0.3090, -0.9511)).So,[x_K = frac{3 times 0.3090 + 7 times 1}{3 + 7} = frac{0.927 + 7}{10} = frac{7.927}{10} = 0.7927][y_K = frac{3 times (-0.9511) + 7 times 0}{10} = frac{-2.8533 + 0}{10} = -0.2853]So, (K) is at approximately ((0.7927, -0.2853)).Now, I need to find point (L) on (CD) such that (angle LAE + angle KCD = 108^circ).First, let me find the coordinates of (C) and (D):(C: (-0.8090, 0.5878))(D: (-0.8090, -0.5878))So, side (CD) is a vertical line segment from ((-0.8090, 0.5878)) to ((-0.8090, -0.5878)).Let me parameterize point (L) on (CD). Let me denote (L) as ((-0.8090, y_L)), where (y_L) ranges from (0.5878) to (-0.5878).Now, I need to find (y_L) such that (angle LAE + angle KCD = 108^circ).First, let me find (angle LAE). This is the angle at point (A) between points (L) and (E).Similarly, (angle KCD) is the angle at point (C) between points (K) and (D).Let me compute these angles using vectors.First, compute (angle LAE):Vectors (AL) and (AE).Point (A: (1,0))Point (L: (-0.8090, y_L))Point (E: (0.3090, -0.9511))Vector (AL = L - A = (-0.8090 - 1, y_L - 0) = (-1.8090, y_L))Vector (AE = E - A = (0.3090 - 1, -0.9511 - 0) = (-0.6910, -0.9511))The angle between vectors (AL) and (AE) is (angle LAE).The formula for the angle between two vectors is:[cos theta = frac{vec{u} cdot vec{v}}{|vec{u}| |vec{v}|}]So,[cos angle LAE = frac{(-1.8090)(-0.6910) + (y_L)(-0.9511)}{sqrt{(-1.8090)^2 + y_L^2} times sqrt{(-0.6910)^2 + (-0.9511)^2}}]Compute the denominator:[|vec{AL}| = sqrt{(-1.8090)^2 + y_L^2} = sqrt{3.2725 + y_L^2}][|vec{AE}| = sqrt{(-0.6910)^2 + (-0.9511)^2} = sqrt{0.4775 + 0.9046} = sqrt{1.3821} approx 1.175]So,[cos angle LAE = frac{(1.8090 times 0.6910) - (0.9511 y_L)}{sqrt{3.2725 + y_L^2} times 1.175}]Compute (1.8090 times 0.6910 approx 1.250)So,[cos angle LAE approx frac{1.250 - 0.9511 y_L}{1.175 sqrt{3.2725 + y_L^2}}]Similarly, compute (angle KCD):Vectors (CK) and (CD).Point (C: (-0.8090, 0.5878))Point (K: (0.7927, -0.2853))Point (D: (-0.8090, -0.5878))Vector (CK = K - C = (0.7927 - (-0.8090), -0.2853 - 0.5878) = (1.6017, -0.8731))Vector (CD = D - C = (-0.8090 - (-0.8090), -0.5878 - 0.5878) = (0, -1.1756))The angle between vectors (CK) and (CD) is (angle KCD).Using the dot product formula:[cos angle KCD = frac{vec{CK} cdot vec{CD}}{|vec{CK}| |vec{CD}|}]Compute the dot product:[(1.6017)(0) + (-0.8731)(-1.1756) = 0 + 1.027 approx 1.027]Compute (|vec{CK}|):[sqrt{(1.6017)^2 + (-0.8731)^2} = sqrt{2.565 + 0.762} = sqrt{3.327} approx 1.824]Compute (|vec{CD}|):[sqrt{0^2 + (-1.1756)^2} = 1.1756]So,[cos angle KCD = frac{1.027}{1.824 times 1.1756} approx frac{1.027}{2.147} approx 0.478]Thus,[angle KCD approx cos^{-1}(0.478) approx 61.3^circ]Wait, but we know that (angle LAE + angle KCD = 108^circ). So, if (angle KCD approx 61.3^circ), then (angle LAE approx 108^circ - 61.3^circ = 46.7^circ).But I need to find (y_L) such that (angle LAE approx 46.7^circ).So, let's set up the equation:[cos 46.7^circ approx frac{1.250 - 0.9511 y_L}{1.175 sqrt{3.2725 + y_L^2}}]Compute (cos 46.7^circ approx 0.687).So,[0.687 approx frac{1.250 - 0.9511 y_L}{1.175 sqrt{3.2725 + y_L^2}}]Multiply both sides by (1.175 sqrt{3.2725 + y_L^2}):[0.687 times 1.175 sqrt{3.2725 + y_L^2} approx 1.250 - 0.9511 y_L]Compute (0.687 times 1.175 approx 0.808).So,[0.808 sqrt{3.2725 + y_L^2} approx 1.250 - 0.9511 y_L]Let me square both sides to eliminate the square root:[(0.808)^2 (3.2725 + y_L^2) approx (1.250 - 0.9511 y_L)^2]Compute (0.808^2 approx 0.6529).Left side:[0.6529 times (3.2725 + y_L^2) approx 0.6529 times 3.2725 + 0.6529 y_L^2 approx 2.136 + 0.6529 y_L^2]Right side:[(1.250)^2 - 2 times 1.250 times 0.9511 y_L + (0.9511 y_L)^2 approx 1.5625 - 2.3778 y_L + 0.9046 y_L^2]So, the equation becomes:[2.136 + 0.6529 y_L^2 approx 1.5625 - 2.3778 y_L + 0.9046 y_L^2]Bring all terms to the left side:[2.136 + 0.6529 y_L^2 - 1.5625 + 2.3778 y_L - 0.9046 y_L^2 approx 0]Simplify:[(2.136 - 1.5625) + (0.6529 - 0.9046) y_L^2 + 2.3778 y_L approx 0][0.5735 - 0.2517 y_L^2 + 2.3778 y_L approx 0]Multiply both sides by -1 to make it easier:[0.2517 y_L^2 - 2.3778 y_L - 0.5735 approx 0]Now, solve this quadratic equation for (y_L):[0.2517 y_L^2 - 2.3778 y_L - 0.5735 = 0]Using the quadratic formula:[y_L = frac{2.3778 pm sqrt{(2.3778)^2 - 4 times 0.2517 times (-0.5735)}}{2 times 0.2517}]Compute discriminant:[D = (2.3778)^2 - 4 times 0.2517 times (-0.5735) approx 5.653 + 0.578 approx 6.231]So,[y_L = frac{2.3778 pm sqrt{6.231}}{0.5034} approx frac{2.3778 pm 2.496}{0.5034}]Compute both solutions:1. (y_L = frac{2.3778 + 2.496}{0.5034} approx frac{4.8738}{0.5034} approx 9.68)2. (y_L = frac{2.3778 - 2.496}{0.5034} approx frac{-0.1182}{0.5034} approx -0.235)Now, since point (L) is on (CD), which has (y)-coordinates ranging from (0.5878) to (-0.5878), the solution (y_L approx 9.68) is outside this range, so we discard it. Thus, (y_L approx -0.235).So, point (L) is at ((-0.8090, -0.235)).Now, I need to find (CL). Since (C) is at ((-0.8090, 0.5878)) and (L) is at ((-0.8090, -0.235)), the distance (CL) is the vertical distance between these two points.Compute (CL):[CL = |0.5878 - (-0.235)| = |0.5878 + 0.235| = 0.8228]But wait, in our coordinate system, the side length (AB) is not 10, but the distance between (A(1,0)) and (B(cos 72^circ, sin 72^circ)). Let me compute the actual side length.Compute distance (AB):[AB = sqrt{(1 - cos 72^circ)^2 + (0 - sin 72^circ)^2}][= sqrt{(1 - 0.3090)^2 + (-0.9511)^2}][= sqrt{(0.6910)^2 + (0.9511)^2}][= sqrt{0.4775 + 0.9046} = sqrt{1.3821} approx 1.175]So, in our coordinate system, the side length is approximately (1.175). But in the problem, the side length is (10x), so we need to scale our coordinates accordingly.Let me denote the scaling factor as (s), such that (1.175 s = 10x). But since we set (R = 1), and the side length is (1.175), to make the side length (10), we need (s = 10 / 1.175 approx 8.506).But actually, since we set (R = 1), the side length is (1.175). So, in our coordinate system, (CL approx 0.8228), which corresponds to (0.8228 times s) in the actual problem.Wait, no, actually, in our coordinate system, the side length is (1.175), which we set as (10x). So, (1.175 = 10x), so (x = 0.1175).But we found (CL approx 0.8228) in our coordinate system. To find (CL) in terms of (x), we need to scale it.Wait, actually, in our coordinate system, the side length is (1.175), which is equal to (10x). So, (x = 1.175 / 10 = 0.1175).But (CL) in our coordinate system is (0.8228), which is (0.8228 / 1.175) times the side length.Wait, no, actually, in our coordinate system, the side length is (1.175), which is equal to (10x). So, (x = 0.1175).But (CL) in our coordinate system is (0.8228), which is a length in the same units as the side length. So, to express (CL) in terms of (x), we have:Since (10x = 1.175), then (x = 0.1175).Thus, (CL = 0.8228) in our coordinate system is equivalent to (0.8228 / 1.175 times 10x).Wait, no, that's not correct. Let me think again.In our coordinate system, the side length is (1.175), which corresponds to (10x) in the problem. So, the scaling factor is (1.175 = 10x), so (x = 0.1175).But (CL) in our coordinate system is (0.8228), which is a length in the same units. So, to find (CL) in terms of (x), we have:Since (1.175 = 10x), then (1 unit = 10x / 1.175).Thus, (CL = 0.8228 times (10x / 1.175) approx 0.8228 times 8.506x approx 7x).Wait, that makes sense because (CL) is approximately (7x), and (AB = 10x), so the ratio (CL:AB = 7:10 = 0.7).Therefore, the ratio (CL:AB) is (0.7).
question:Consider A and B are two other natural numbers. If A divides by 13 is 33 with a remainder of B, find A that makes B the largest.
answer:First, I recognize that when a number ( A ) is divided by 13, it can be expressed as:[A = 13q + B]where ( q ) is the quotient and ( B ) is the remainder.Given that the quotient ( q ) is 33, the equation becomes:[A = 13 times 33 + B][A = 429 + B]Since ( B ) is the remainder when dividing by 13, it must satisfy:[0 leq B < 13]To maximize ( B ), the largest possible value is 12. Substituting ( B = 12 ) into the equation:[A = 429 + 12][A = 441]Therefore, the value of ( A ) that makes ( B ) the largest is 441.
question:Mrs. Hilt has three pennies, two dimes, two nickels, five quarters, and one dollar coin. Jacob has four pennies, one nickel, one dime, three quarters, two half-dollars and two dollars. How much money does Jacob have more than Mrs. Hilt?
answer:First, calculate the total amount of money Mrs. Hilt has by summing the values of each type of coin she possesses. Then, do the same for Jacob. Finally, subtract Mrs. Hilt's total from Jacob's total to find the difference.
question:The sides of a rectangular field are in the ratio 3 : 4. If the area of the field is 8112 sq. m, what is the cost of fencing the field @ 25 paise per meter?
answer:First, I need to determine the actual lengths of the sides of the rectangular field based on the given ratio of 3:4. I'll represent the sides as 3x and 4x, where x is a common multiplier.Next, I'll use the area of the field to find the value of x. The area of a rectangle is calculated by multiplying its length and width, so I'll set up the equation:8112 = (3x) × (4x)Simplifying this, I get:8112 = 12x²Solving for x²:x² = 8112 / 12x² = 676Taking the square root of both sides:x = √676x = 26Now that I have the value of x, I can find the actual lengths of the sides:Length = 3x = 3 × 26 = 78 metersWidth = 4x = 4 × 26 = 104 metersWith the lengths of the sides known, I can calculate the perimeter of the rectangle, which is the total length of fencing needed:Perimeter = 2 × (Length + Width)Perimeter = 2 × (78 + 104)Perimeter = 2 × 182Perimeter = 364 metersFinally, I'll calculate the total cost of fencing. The cost per meter is 25 paise, which is equivalent to 0.25 rupees. Therefore:Total Cost = Perimeter × Cost per MeterTotal Cost = 364 × 0.25Total Cost = 91 rupeesSo, the cost of fencing the field is 91 rupees.
question:In the summer of 2017, the beautiful Qinghai became a hot tourist destination. When A, B, and C, three tourists, were asked if they had visited Qinghai Lake, the hundred-mile rapeseed flower sea in Haibei, and the Tea Card Sky Realm, the following responses were given: A said: I have visited more places than B, but I have not visited the hundred-mile rapeseed flower sea in Haibei; B said: I have not visited the Tea Card Sky Realm; C said: The three of us have visited the same place. From this, it can be determined that the place B has visited is ______.
answer:Okay, so I'm trying to figure out where B has visited based on the statements from A, B, and C. Let me break it down step by step.First, let's list out the places mentioned: Qinghai Lake, the hundred-mile rapeseed flower sea in Haibei, and the Tea Card Sky Realm. So, there are three places in total.Now, let's look at what each person said:- **A** said: "I have visited more places than B, but I have not visited the hundred-mile rapeseed flower sea in Haibei."- **B** said: "I have not visited the Tea Card Sky Realm."- **C** said: "The three of us have visited the same place."Alright, starting with B's statement: B has not visited the Tea Card Sky Realm. So, B could have visited either Qinghai Lake or the hundred-mile rapeseed flower sea in Haibei.Next, A's statement: A has visited more places than B, and A has not visited the hundred-mile rapeseed flower sea in Haibei. Since A has visited more places than B, and there are three places in total, let's consider the possibilities.If B has visited one place, then A must have visited at least two places. But A has not visited the hundred-mile rapeseed flower sea, so A could have visited Qinghai Lake and the Tea Card Sky Realm. That would mean A has visited two places, which is more than B's one place.Now, C's statement says that all three have visited the same place. That means there must be at least one place that all three have visited. Given that A has visited Qinghai Lake and the Tea Card Sky Realm, and B has not visited the Tea Card Sky Realm, the only place they could all have visited is Qinghai Lake.So, putting it all together:- B has not visited the Tea Card Sky Realm.- A has visited more places than B and has not visited the hundred-mile rapeseed flower sea.- Therefore, A must have visited Qinghai Lake and the Tea Card Sky Realm.- Since all three have visited the same place, that place must be Qinghai Lake.So, B has visited Qinghai Lake.