Find the smallest number which should be multiplied with 520 to make it a perfect square.
Options:
(A) 30
(B) 120
(C) 55
(D) 35
(E) None of these
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520 = 26 * 20 = 2 * 13 * 22 * 5 = 23 * 13 * 5
Required smallest number = 2 * 13 * 5 = 130
130 is the smallest number which should be multiplied with 520 to make it a perfect squar So the answer is: (E).
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The average of first 10 odd numbers is?
Options:
(A) 11
(B) 10
(C) 88
(D) 176
(E) 12
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Sum of 10 odd no. = 100
Average = 100/10 = 10 So the answer is: (B).
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Jack has two dice, one has six equally probable sides, labeled 1, 2, 3, 4, 5, 6, and the other has seven equally probable sides, labeled 1, 2, 3, 4, 5, 6, 7. If Jack rolls both dice what is the probability that both of the number's sum will be 13?
Options:
(A) 3/14
(B) 2/7
(C) 1/3
(D) 1/42
(E) 12/21
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Both Dice addition result is 13 = (6+7)
Probability that the number on first die is 6 = 1/6
Probability that the number on Second die is 7 = 1/7
Probability that Both Dice addition result is 13 = 1/6 * 1/7 = 1/42 So the answer is: (D).
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