Rationale: I think answer on this one should be D too. Since we know that 14^7>17^4, as Will said one should always check if the number is positive.
The answer: (D)
Question: What is the units digit of the expression 14^717^4?
Options:
(A) 0
(B) 3
(C) 4
(D) 8
(E) 6
Reasoning: P(at least one gold ball) = 1 - P(no golf ball, so 2 ping pong balls) = 1- 2/5*1/4 = 9/10.
Ans: (D)
Question: In a jar there are 3 golf balls and 2 ping pong balls. What is the probability of drawing at least one golf ball when drawing two consecutive balls randomly?
Options:
(A) 1/4
(B) 1/2
(C) 3/5
(D) 9/10
(E) 16/20
Rationale: The number of eggs must be one more than a number that is divisible by 2, 3, 4, 5, and 6 since each of these numbers leave a remainder of 1. For this to be true one less than the number must be divisible by 5, 4, and 3 (6 is 2*3 and 2 is a factor of 4 so they will automatically be a factor). 5 * 4 * 3 = 60. Then you just must find a multiple of 60 such that 60 * n + 1 is divisible by 7. 61 / 7, 121 / 7, 181 / 7, 241 / 7 all leave remainders but 301 / 7 doesn't.
The answer: (B)
Question: John has some chickens that have been laying him plenty of eggs. He wants to give away his eggs to several of his friends, but he wants to give them all the same number of eggs. He figures out that he needs to give 7 of his friends eggs for them to get the same amount, otherwise there is 1 extra egg left.
What is the least number of eggs he needs for this to be true?
Options:
(A) 201
(B) 301
(C) 401
(D) 101
(E) 501
Reasoning: 10 books can be rearranged in 10! ways consider the two books taken as a pair then number of favourable ways of getting these two books together is 9! 2!
Required probability = 1/5
Ans: (C)
Question: 10 books are placed at random in a shelf. The probability that a pair of books will always be together is?
Options:
(A) 1/6
(B) 1/7
(C) 1/5
(D) 1/9
(E) 1/2
Rationale: I will go with E (pending elements to match is 2^2*3^2*13^1 = 468
The answer: (E)
Question: If 2^4, 3^3, and 13^3 are factors of the product of 1,452 and w, where w is a positive integer, what is the smallest possible value of w?
Options:
(A) 198
(B) 288
(C) 363
(D) 396
(E) 468
Rationale: In the beginning it is 99 pounds water and 1 pound other stuff. At the end the 1 pound other stuff is 2 percent so the total weight is 50 pounds. 50 pounds - 1 pound other stuff = 49 pounds water. So 99 pounds - 49 pounds = 50 pounds water lost.
The answer: (D)
Question: There is a 100 pound watermelon laying out in the sun. 99 percent of the watermelon's weight is water. After laying out for a few hours 98 percent of the watermelon's weight is water.
How much water evaporated?
Options:
(A) 20
(B) 30
(C) 40
(D) 50
(E) 10