Reasoning: 3/8 * 2/7 = 6/56
1-(6/56) = 50/56 = 25/28
Ans: (D)
Question: A shipment of 8 TV sets contains 5 black and white sets and 3 color sets. If 2 TV sets are to be chosen at random from this shipment, what is the probability that at least 1 of the 2 sets chosen will be a black and white set?
Options:
(A) 1/7
(B) 1/4
(C) 5/14
(D) 25/28
(E) 13/28
Rationale: 1/18 + 1/30 = 8/90 = 4/45
45/4 = 11 *2 = 22 1/2 days
The answer: (B)
Question: A can do a job in 18 days and B can do it in 30 days. A and B working together will finish twice the amount of work in ------- days?
Options:
(A) 22 1/8
(B) 22 1/2
(C) 22 1/1
(D) 22 1/5
(E) 22 1/9
Reasoning: 7 = 3 blue balls + 12 / 3
Ans: (D)
Question: There are 15 balls in a jar. You take out 3 blue balls without putting them back inside, and now the probability of pulling out a blue ball is 1/3. How many blue balls were there in the beginning?
Options:
(A) 12.
(B) 9.
(C) 8.
(D) 7.
(E) 6.
Rationale: Work done by X in 1 day = 1/20
Work done by Y in 1 day = 1/16
Work done by Y in 12 days = 12/16 = 3/4
Remaining work = 1 3/4 = 1/4
Number of days in which X can finish the remaining work = (1/4) / (1/20) = 5
The answer: (D)
Question: X can finish a work in 20 days. Y can finish the same work in 16 days. Y worked for 12 days and left the job. how many days does X alone need to finish the remaining work?
Options:
(A) 2
(B) 3
(C) 9
(D) 5
(E) 8
Reasoning: Divisibility rule of 3: The sum of the digits of the number should be divisible by 3
Option A: 10395, Sum = 18. Divisible by 3
Option B: 41714, Sum = 17, Not divisible by 3. Hence the number 41714 is also not divisible by 3
Option C: 15354, Sum = 18, Divisible by 3
Option D: 30708, Sum = 18, Divisible by 3
Option E: 29313, Sum = 18, Divisible by 3
Ans: (B)
Question: Which of the following is not divisible by 3?
Options:
(A) 10,395
(B) 41,714
(C) 15,354
(D) 30,708
(E) 29,313
Reasoning: 8 * 37 7 * 40 = 16
Ans: (E)
Question: The average of eight results is 37 and that of the first seven is 40. The eighth result is?
Options:
(A) 25
(B) 30
(C) 12
(D) 37
(E) 16