q: 150 is increased by 40%. Find the final number.
Options:
(A) 200
(B) 210
(C) 180
(D) 190
(E) 220
a: Final number = Initial number + 40%(original number) = 150 + 40%(150) = 150 + 60 = 210. The answer is (B).
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q: If six persons sit in a row, then the probability that three particular persons are always together is?
Options:
(A) 1/5
(B) 1/4
(C) 1/9
(D) 1/6
(E) 1/1
a: Six persons can be arranged in a row in 6! ways. Treat the three persons to sit together as one unit then there four persons and they can be arranged in 4! ways. Again three persons can be arranged among them selves in 3! ways. Favourable outcomes = 3!4! Required probability = 3!4!/6! = 1/5 The answer is (C).
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q: How much more would Rs.40000 fetch, after two years, if it is put at 20% p.a. compound interest payable half yearly than if is put at 20% p.a. compound interest payable yearly?
Options:
(A) 482
(B) 725
(C) 964
(D) 837
(E) 923
a: 40000(11/10)4 - 40000(6/5)2 = 964 The answer is (C).
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q: A car finishes a journey in nine hours at the speed of 80 km/hr. If the same distance is to be covered in six hours how much more speed does the car have to gain?
Options:
(A) 8 km/hr
(B) 40 km/hr
(C) 12 km/hr
(D) 16 km/hr
(E) None of these
a:
Distance covered by the car = 80 9 = 720 km
\ Speed = 7206 = 120 km/hr
\ Speed gain = 120 80 = 40 km/hr The answer is (B).
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