There are 24 distinct numbers in set M, there are 28 distinct numbers in set N, and there are 12 distinct numbers that are in both sets M and N. Set H is the set containing the elements that are in at least one of sets M and N. How many elements are in set H?
Options:
(A) 39
(B) 40
(C) 51
(D) 58
(E) 63
Answer and stream of consciousness: (B)
Stream of consciousness: {Total} = {M} + {N} - {Both}
{Total} = 24 + 28 - 12 = 40.

The no. of girls in a class are seven times the no. of boys, which value cannever be the of total students?
Options:
(A) 3
(B) 5
(C) 8
(D) 9
(E) 11
Answer and stream of consciousness: (C)
Stream of consciousness: Let the boys are X, then girls are 7X, total = X+7X = 8X
So it should be multiple of 8, 30 is not a multiple of 8.

A and B can do a work in 10 days and 15 days respectively. A starts the work and B joins him after 2 days. In how many days can they complete the remaining work?
Options:
(A) 6 days
(B) 2 days
(C) 4 4/5 days
(D) 3 days
(E) 9 days
Answer and stream of consciousness: (C)
Stream of consciousness: Work done by A in 2 days = 2/10 = 1/5
Remaining work = 4/5
Work done by both A and B in one day = 1/10 + 1/15 = 5/30 = 1/6
Remaining work = 4/5 * 6/1 = 24/5 = 4 4/5 days.

Interest Rate: 4% monthly Starting Balance: 124 Time Passed: 4 months How much interest has accrued if calculated as compound interest? What is the new total balance?
Options:
(A) 21 & 145
(B) 22 & 146
(C) 23 & 145
(D) 20 & 140
(E) None
Answer and stream of consciousness:
(A)
Stream of consciousness: Compound Interest: Total Balance = P(1 + R)T P = principle = starting balance = $124 R = interest rate = 4% T = time = 4 years Total balance = principle (1 + interest rate)time = 124 (1 + (4 / 100))4 = 145 Interest accrued = total balance - starting balance = 145 - 124 = 21