Problem on Numbers-11

If one-third of one-fourth of a number is 15, then three-tenth of that number is:
(A) 35 (B) 36 (C) 45 (D) 54
Answer: D

Description:
Let the number be X.
Then 1/3 of 1/4 of X =15*12=180
So Required number = [3*180]/10=54.