Rationale: Final number = Initial number + 50%(original number) = 70 + 50%(70) = 70 + 35 = 105.
The answer: (C)
Question: 70 is increased by 50%. Find the final number.
Options:
(A) 100
(B) 110
(C) 105
(D) 30
(E) 160
Reasoning: The length of cube Q = 1;
The length of cube P = 2;
The ratio of the volume of cube Q to the volume of cube P = 1^3/2^3 = 1/8.
Ans: (A)
Question: If the length of an edge of cube P is twice the length of an edge of cube Q, what is the ratio of the volume of cube Q to the volume of cube P?
Options:
(A) 1/8
(B) 1/4
(C) 1/3
(D) 1/7
(E) 1/9
Rationale: Other number = (12 x 520)/480 = 13.
The answer: (A)
Question: The H.C.F. of two numbers is 12 and their L.C.M. is 520. If one of the numbers is 480, then the other is:
Options:
(A) 13
(B) 18
(C) 21
(D) 24
(E) 38
Reasoning: 1 to 9 = 9 * 9 = 81
1 to 5 = 5 * 10 = 50
5 to 9 = 5 * 8 = 40
5th = 50 + 40 = 90 81 = 9
Ans: (A)
Question: The average of 9 observations was 9, that of the 1st of 5 being 10 and that of the last 5 being 8. What was the 5th observation?
Options:
(A) 9
(B) 8
(C) 7
(D) 6
(E) 2
Rationale: Population after n years = P [1 + (R/100)]2
Population after 2 years = 140000 * [1 + 6/100]2 = (160000 x 53/50 x 53/50) = 157304
The answer: (E)
Question: he population of a city is 140,000. If it increases at the rate of 6% per annum, then what will be its population 2 years hence?
Options:
(A) 1797787
(B) 1597723
(C) 159776
(D) 159728
(E) 157304
Rationale: Given Exp. = (12)3 x 64 = (12)3 x 64 = (12)2 x 62 = (72)2 = 5184
432 12 x 62
The answer: (E)
Question: Find the value of y from (12)^3 x 6^4432 =y?
Options:
(A) 4363
(B) 4765
(C) 4879
(D) 6789
(E) 5184