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question:A shop offered a 32% discount for every shirt. Smith bought a shirt at a discounted price, and the shop's original selling price was Rs. 955.88. What was the discounted price Smith paid for the shirt?
answer:To find the discounted price Smith paid for the shirt, we need to calculate the discount amount and subtract it from the original selling price. The discount rate is 32%, so we can calculate the discount amount as follows: Discount Amount = (Discount Rate) x (Original Selling Price) Discount Amount = (32/100) x Rs. 955.88 Now, let's calculate the discount amount: Discount Amount = 0.32 x Rs. 955.88 Discount Amount = Rs. 305.8816 Now that we have the discount amount, we can find the discounted price by subtracting the discount amount from the original selling price: Discounted Price = Original Selling Price - Discount Amount Discounted Price = Rs. 955.88 - Rs. 305.8816 Let's calculate the discounted price: Discounted Price = Rs. 955.88 - Rs. 305.8816 Discounted Price = Rs. 649.9984 Since prices are usually rounded to the nearest currency unit, the discounted price Smith paid for the shirt would be approximately Rs. boxed{650.00} .
question:a,b,c are the opposite sides of angles A,B,C in triangle ABC, given asin left(ABright)=left(cbright)sin A.<br/>(1) Find A;<br/>(2) If point D lies on segment BC, ∠ADC=frac{π}{3}, AD=3, and the area of triangle ABC is 3sqrt{3}, find the perimeter of triangle ABC.
answer:# Solution: Part 1: Finding A Given asin(A-B)=(c-b)sin A, we apply the sine rule to transform the equation: 1. By the sine rule, we have frac{a}{sin A} = frac{b}{sin B} = frac{c}{sin C}. 2. Therefore, asin(A-B)=(c-b)sin A becomes sin Asin(A-B)=(sin C-sin B)sin A. 3. Since sin A > 0, we can simplify to sin(A-B)=sin C-sin B. 4. This further simplifies to sin(A-B)=sin(A+B)-sin B. 5. Expanding both sides gives sin Acos B-cos Asin B=sin Acos B+cos Asin B-sin B. 6. Simplifying, we get 2sin Bcos A=sin B. 7. Since 0 < B < pi, implying sin B > 0, we divide both sides by sin B to get cos A=frac{1}{2}. 8. Given 0 < A < pi, we conclude A=frac{pi}{3}. Therefore, the angle A is boxed{frac{pi}{3}}. Part 2: Finding the Perimeter of triangle ABC Given AD=3, ∠ADC=frac{pi}{3}, and the area of triangle ABC is 3sqrt{3}: 1. The area S can be expressed as S=frac{1}{2}ADcdot[CDsin∠ADC+BDsin(pi-∠ADC)]=frac{a}{2}cdot ADcdotfrac{sqrt{3}}{2}=frac{3sqrt{3}}{4}a. 2. Since S=3sqrt{3}, equating both expressions for S gives a=4. 3. Also, S=3sqrt{3}=frac{1}{2}bcdot csin A leads to bc=12. 4. Using the cosine rule a^{2}=b^{2}+c^{2}-2bccos A, we find a^{2}=(b+c)^{2}-3bc. 5. Solving for b+c gives b+c=sqrt{a^{2}+3bc}=2sqrt{13}. Therefore, the perimeter of triangle ABC is boxed{4+2sqrt{13}}.
question:Evaluate the integral int_{1}^{1}{(sin x+1)dx}. A: 0 B: 2 C: 2+2cos 1 D: 22cos 1
answer:**Analysis** This question mainly tests the calculation of definite integrals and the application of derivative formulas in reverse, which is a basic type of problem. The key is to accurately find the antiderivative of the integrand. **Solution** The value of the integral is (x-cos x)|_{-1}^{1}=(1-cos 1)-(-1-cos (-1))=2-cos 1+cos 1=2. Therefore, the correct choice is boxed{B}.
question:a triangle ABC, the sides are in the ratio 3:4:5. If the perimeter of the triangle is 60 cm, find the lengths of each side. A) 15 cm, 20 cm, 25 cm B) 12 cm, 16 cm, 20 cm C) 10 cm, 15 cm, 20 cm D) 9 cm, 12 cm, 15 cm
answer:1. Let the sides of the triangle ABC be 3x, 4x, and 5x respectively. 2. Since the perimeter is the sum of all sides, we have: [ 3x + 4x + 5x = 60 text{ cm} ] 3. Simplify to find x: [ 12x = 60 text{ cm} implies x = frac{60}{12} = 5 text{ cm} ] 4. Now find the lengths of the sides: - Side AB = 3x = 3 times 5 = 15 cm - Side BC = 4x = 4 times 5 = 20 cm - Side AC = 5x = 5 times 5 = 25 cm Conclusion: The lengths of the sides are 15 cm, 20 cm, and 25 cm respectively, with 15text{ cm, 20text{ cm}, 25text{ cm}}. The final answer is boxed{A}