4/15 of 5/7 of a number is greater than 4/9 of 2/5 of the same number by 8.
What is half of that number?  Choose the correct choice from the following choices:  A) 305  B) 315  C) 345  D) 325  E) 335

Rationale: let the number be x . then 4 / 15 of 5 / 7 of x - 4 / 9 of 2 / 5 of x = 8  4 / 21 x - 8 / 45 x = 8 ( 4 / 21 - 8 / 45 ) x = 8  ( 60 - 56 ) / 315 x = 8  4 / 315 x = 8 x = ( 8 * 315 ) / 4 = 630  1 / 2 x = 315 hence required number = 315 answer is b .
Answer: B