q: What is the sum of all the prime numbers greater than 50 but less than 70?
Options:
(A) 249
(B) 248
(C) 246
(D) 240
(E) 241
a: Stream of consciousness: Required sum = (53 + 59 + 61 + 67 ) = 240
Note: 1 is not a prime number The answer is (D).

question: X can finish a work in 30 days. Y can finish the same work in 15 days. Yworked for 10 days and left the job. how many days does X alone need to finish the remaining work?
Options:
(A) 3
(B) 10
(C) 6
(D) 8
(E) 9
answer: Stream of consciousness: Work done by X in 1 day = 1/30
Work done by Y in 1 day = 1/15
Work done by Y in 10 days = 10/15 = 2/3
Remaining work = 1 2/3 = 1/3
Number of days in which X can finish the remaining work = (1/3) / (1/30) = 10 The answer is (B).

q: A 600 meter long train crosses a signal post in 40 seconds. How long will it take to cross a 3 kilometer long bridge, at the same speed?
Options:
(A) 4 min
(B) 8 min
(C) 9 min
(D) 6 min
(E) 1 min
a: Stream of consciousness: S = 600/40 = 15 mps
S = 3600/15 = 240 sec = 4 min The answer is (A).

question: P and Q invested in a shop. The profits were divided in the ratio of 2 : 3 respectively. If P invested Rs. 40,000, the amount invested by Q is:
Options:
(A) 35000
(B) 40000
(C) 50000
(D) 60000
(E) None
answer: Stream of consciousness: Suppose Q invested Rs. y. Then, 40000/y = 2/3 or y = [40000 x 3 / 2] = 60000. The answer is (D).

q: The length of a rectangle is increased by 25% and its breadth is decreased by 15%. What is the effect on its area?
Options:
(A) 1288
(B) 1299
(C) 10625
(D) 10000
(E) 2887
a: Stream of consciousness: 100 * 100 = 10000
125 * 85 = 10625 The answer is (C).

q: P can do a work in 24 days. Q can do the samework in 9 days & R can do the same work in 12 days. Q & R start the work and leave after 3 days. P finishes the remaining work in how many days.
Options:
(A) 8
(B) 10
(C) 14
(D) 16
(E) 19
a:
Stream of consciousness: Work done by P in 1 day = 1/24
Work done by Q in 1 day = 1/9
Work done by R in 1 day = 1/12
Work done by Q and R in 1 day = 1/9 + 1/12 = 7/36
Work done by Q and R in 3 days = 37/36 = 7/12
Remaining work = 1 7/12 = 5/12
Number of days in which P can finish the remaining work = (5/12) / (1/24) = 10 The answer is (B).