q: Find the least number must be subtracted from 427398 so that remaining no.is divisible by 15?
Options:
(A) 1
(B) 3
(C) 5
(D) 6
(E) 7
a: OK... On dividing 427398 by 15 we get the remainder 3, so 3 should be subtracted
The answer is (A).

q: If f(x) = x^3/(x^5 - 1), what is f(1/x) in terms of f(x)?
Options:
(A) -f(x)
(B) 1/f(x)
(C) 2/f(x)
(D) 3/f(x)
(E) f(x)
a: OK... If x = 2 then f(x) = 8/31 and f(1/x) = -8/31 which is equal to -f(x)
The answer is (A).

q: A computer factory produces 4032 computers per month at a constant rate, how many computers are built every 30 minutes assuming that there are 28 days in one month?
Options:
(A) 2.25.
(B) 3.00.
(C) 4.5.
(D) 5.225.
(E) 6.25.
a:
OK... Number of hours in 28 days = 28*24
Number of 30 mins in 28 days = 28*24*2
Number of computers built every 30 mins = 4032/( 28*24*2) = 3
The answer is (B).