q: A boy runs 200 metres in 36 seconds. What is his speed ?
Options:
(A) 20 km/hr
(B) 24 km/hr
(C) 30 km/hr
(D) 32 km/hr
(E) 34 km/hr
a: Stream of consciousness: 200/36 * 18/5 = 20 km/hr The answer is (A).
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q: A 70 cm long wire is to be cut into two pieces so that one piece will be 2/5th of the other, how many centimeters will the shorter piece be?
Options:
(A) 12
(B) 20
(C) 88
(D) 77
(E) 14
a: Stream of consciousness: 1: 2/5 = 5: 2
2/7 * 70 = 20 The answer is (B).
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q: A card shop contains 5 birthday cards, 4 holiday cards, and 3 graduation cards. If three cards are purchased at random from the shop, what is the probability that the three cards will be graduation cards?
Options:
(A) 1/33
(B) 6/264
(C) 1/44
(D) 1/264
(E) 1/1320
a:
Stream of consciousness: It doesn't matter which type of card you choose, so:
Probability of choosing 1st card: 3/12
Probability of choosing 2nd card of the same type: 2/11
Probability of choosing 3rd card of the same type: 1/10
Multiply and you get 1/264 The answer is (D).
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