q: 30 pens and 75 pencils were purchased for 450. If the average price of a pencil was 2.00, find the average price of a pen.
Options:
(A) 10
(B) 11
(C) 12
(D) 13
(E) 14
a: Stream of consciousness: Since average price of a pencil = 2
∴ Price of 75 pencils = 150
∴ Price of 30 pens = (450 – 150) = 300
∴ Average price of a pen = 360⁄60 = 10 The answer is (A).
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q: Two persons A and B can complete a piece of work in 18 days and 24 days respectively. If they work together, what part of the work will be completed in 2 days?
Options:
(A) 7/36
(B) 9/35
(C) 4/37
(D) 8/35
(E) 5/3
a: Stream of consciousness: A's one day's work = 1/18
B's one day's work = 1/24
(A + B)'s one day's work = 1/18 + 1/24 = 7/72
The part of the work completed in 3 days = 2 (7/72) = 7/36. The answer is (A).
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q: A car traveled from San Diego to San Francisco at an average speed of 66 miles per hour. If the journey back took twice as long, what was the average speed of the trip?
Options:
(A) 24.
(B) 32.
(C) 36.
(D) 42.
(E) 44.
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
Stream of consciousness: Let the time taken be = x
One way distance = 66x
Total distance traveled = 2 * 66x = 132x
Total time taken = x + 2x = 3x
Average speed = 132x/3x = 44 The answer is (E).
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