Find the odd man out
253, 136, 352, 327, 631, 244
Options:
(A) 327
(B) 136
(C) 352
(D) 631
(E) 531
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The sum all three digits comes to 10 except 327 So the answer is: (A).
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A 200 meter long train crosses a man standing on the platform in 9 sec. What is the speed of the train?
Options:
(A) 228
(B) 108
(C) 1266
(D) 188
(E) 80
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S = 200/9 * 18/5 = 80 kmph So the answer is: (E).
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In b is a positive integer smaller than 200 and (14b)/60 is an integer, then b has how many different positive prime factors?
Options:
(A) 2
(B) 3
(C) 5
(D) 6
(E) 8
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7b/30 tells us that b is a factor of 30, which has 2, 3, and 5 as its prime factors. Each of them is distinct. Moreover, all multiples of 30 less than 200 can be derived by multiplying these prime factors alone. Thus, number of different prime factors is 3. So the answer is: (B).
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