3 friends alice , bond and charlie divide $ 1105 amongs them in such a way that if $ 10 , $ 20 and $ 15 are removed from the sums that alice , bond and charlie received respectively , then the share of the sums that they got will be in the ratio of 11 : 18 : 24 . how much did charlie receive ?
Choices:  A) $ 495  B) $ 510  C) $ 480  D) $ 375  E) $ 360

Rationale: explanatory answer let the sums of money received by a , b and c be x , y and z respectively . then x - 10 : y - 20 : z - 15 is 11 a : 18 a : 24 a when $ 10 , $ 20 and $ 15 are removed , we are removing a total of $ 45 from $ 1105 . therefore , 11 a + 18 a + 24 a = 1105 - 45 = 1060 i . e . , 53 a = 1060 or a = 20 . we know that z - 15 = 24 a = 24 * 20 = 480 therefore , z = 480 + 15 = $ 495 correct choice is ( a )
Answer: A