An analyst will recommend a combination of 3 industrial stocks, 2 transportation stocks, and 2 utility stocks. If the analyst can choose from 4 industrial stocks, 5 transportation stocks, and 3 utility stocks, how many different combinations of 7 stocks are possible?
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Options:
(A) 12
(B) 19
(C) 60
(D) 180
(E) 720

4C3 * 5C2 * 3C2 = 4*60*3 = 720. So the answer is: (E).

At what rate percent on simple interest will a sum of money double itself in 30 years?
Options:
(A) 3 1/3%
(B) 3 1/8%
(C) 3 6/3%
(D) 9 1/3%
(E) 3 3/3%

P = (P*30*R)/100
R = 3 1/3% So the answer is: (A).

3 candidates in an election and received 1136, 7636 and 11628 votes respectively. What % of the total votes did the winningcandidate got in that election?
Options:
(A) 45%
(B) 50%
(C) 57%
(D) 59%
(E) 62

Total number of votes polled = (1136 + 7636 + 11628) = 20400
So, Required percentage = 11628/20400 * 100 = 57% So the answer is: (C).

A man rows his boat 85 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?
Options:
(A) 7 kmph
(B) 4 kmph
(C) 4 kmph
(D) 8 kmph
(E) 5 kmph

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
Speed downstream = d/t = 85/(2 1/2) = 34 kmph
Speed upstream = d/t = 45/(2 1/2) = 18 kmph
The speed of the stream = (34 - 18)/2 = 8 kmph So the answer is: (D).