Question: In the expression 51840/x^4, for which of the following values of x will the expression NOT be an integer?
Options:
(A) 1/2
(B) 1
(C) 2
(D) 3
(E) 5
Ans: (E)
CoT: We can straightaway eliminate A & B, since the expression will always yields an integer for those values
Out of C, D, and E. Let us consider option E. 51840 has only one trailing zero and tens digit is not 5, so It has just one 5 in it. But for the expression to be an integer numerator should have 5^4.
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Question: In a bucket there are 3 green balls and 2 yellow balls. What is the probability of drawing at least one green ball when drawing two consecutive balls randomly?
Options:
(A) 16/20
(B) 9/10
(C) 2/5
(D) 3/5
(E)
Ans: (B)
CoT: P(at least one green) = 1 - P(no green, so 2 yellow) = 1- 2/5*1/4 = 9/10.
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Question: Find the simple interest on Rs.500 for 9 months at 6 paisa per month?
Options:
(A) 288
(B) 270
(C) 999
(D) 278
(E) 121
Ans: (B)
CoT: I = (500*9*6)/100 = 270
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