q: The value of a machine depreciates at the rate of 10% every year. It was purchased 3 years ago. If its present value is Rs. 8748, its purchase price was :
Options:
(A) 12000
(B) 10000
(C) 15000
(D) 20000
(E) 25000
a: Purchase = 8748/(1-10/100^3) = 12000 The answer is (A).
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q: Two trains are traveling on parallel tracks in the same direction. The faster train travels at 120 miles per hour, while the slower train travels at 100 miles per hour. At 2 o'clock the faster train is 10 miles behind the slower one. How far apart are the two trains at 6 o'clock?
Options:
(A) 60 miles
(B) 80 miles
(C) 110 miles
(D) 120 miles
(E) 400 miles
a: Answer = C. 110 miles
Relational speed = 120 - 100 = 20 miles per hour
In 4 hours, difference = 20 * 4 = 120 miles
Fast train trailing 10 miles, so effective difference = 120 - 10 = 110 miles The answer is (C).
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q: Find the wrong number below mentioned series
3,20,50,60,80
Options:
(A) 80
(B) 60
(C) 50
(D) 20
(E) 3
a: 3 is the only prime number or odd number in the series. The answer is (E).
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q: Which among the following is the greatest?
Options:
(A) 2^3^2
(B) 2^2^3
(C) 3^2^3
(D) 3^3^3
(E) 5^3^3
a:
2^3^2 = 29
2^2^3 = 28
3^2^3 = 38
3^3^3 = 327
As 327 > 38, 29 > 28 and 327 > 29. Hence 327 is the greatest among the four. The answer is (D).
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