q: The radius of a cone is 4 m, height 5 m. Find the curved surface area?
Options:
(A) 1
(B) 3
(C) 5
(D) 7
(E) 9
a: Cone curved surface area = πrl = 22/7 × 4 × 5 = 440/7 = 62 6/7
Slant height (l) = √r(power2)+h(power2) = √16+9 = √25 = 5 The answer is (C).
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q: 10 men and 15 women together can complete a work in 3 days. It takes 100 days for one man alone to complete the same work. How many days will be required for one woman alone to complete the same work?
Options:
(A) 1 2/7 days
(B) 64 2/7 days
(C) 1 7/7 days
(D) 1 8/7 days
(E) 62 2/5 days
a: 1 man's 1 day work = 1/100
(10 men + 15 women)'s 1 day work = 1/3
15 women's 1 day work = (1/3- 10/100) = 7/30
1 woman's 1 day work = 7/450
1 woman alone can complete the work in 64 2/7 days. The answer is (B).
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q: A train 495 m long is running at a speed of 63 km/hr. In what time will it pass a bridge 240 m long?
Options:
(A) 39
(B) 40
(C) 41
(D) 42
(E) 43
a: Speed = 63 * 5/18 = 35/2 m/sec
Total distance covered = 495 +240 = 735 m
Required time = 700 * 2/35 = 42 sec The answer is (D).
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q: A man goes into a barbershop and gets a $15 haircut. He pays the barber with a $20 bill, but the barber doesn't have change because it is an especially slow day. The barber goes to the flower shop next to his own and trades the $20 bill for a $10 dollar bill and two $5 bills. Then he gives the man his $5 in change.
Later the lady from the flower shop confronts the barber and tells him that the $20 bill he gave her was counterfeit. The barber agrees and he gives the lady a different $20 bill.
Later that day he tries to figure out how much money he lost. What did he lose?
Options:
(A) $5
(B) $10
(C) $12
(D) $15
(E) $20
a:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
He lost $5. The lady from the flower shop gave him $20 in change, but eventually got $20 back. She broke even. The man who got the haircut gave the barber nothing (except counterfeit money) but got $5 back from the barber. So the barber lost only $5, and gave a free haircut. The answer is (A).
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