q: What will come in place of the x in the following Number series? 46080, 3840, 384, x
Options:
(A) 48
(B) 3
(C) 4
(D) 5
(E) 6
a: 46080 /12 = 3840
3840 /10 = 384
384 /8 = 48 The answer is (A).
--
q: At 15:00 there were 20 students in the computer lab. At 15:03 and every three minutes after that, 4 students entered the lab. If at 15:10 and every ten minutes after that 8 students left the lab, how many students were in the computer lab at 15:44 ?
Options:
(A) 7
(B) 14
(C) 25
(D) 27
(E) 30
a: Initial no of students + 3 * (1 + No of possible 3 minute intervals between 15:03 and 15:44) -
8 *(1 + No of possible 10 minute intervals between 15:10 and 15:44)
20 + 3*14 -8 * 4 = 27 The answer is (D).
--
q: Ravi can do a piece of work in 30 days while Prakash can do it in 40 days. In how many days will they finish it together?
Options:
(A) 19 1/7 days
(B) 16 1/7 days
(C) 14 1/7 days
(D) 17 1/7 days
(E) 13 1/7 days
a: 1/30 + 1/40 = 7/120
120/7 = 17 1/7 days The answer is (D).
--
q: If the given two numbers are respectively 6% and 30% of a third number, then what percentage is the first of the second ?
Options:
(A) 20%
(B) 25%
(C) 18%
(D) 30%
(E) none of these
a:
Here, l = 6 and m = 30
Therefore, first number = l/m x 100% of second number = 6/30 x 100% of second number = 20% of second number The answer is (A).
--