GMAT

题目

GMAT
a family made a down payment of USD75 and borrowed the balance on a set of encyclopedias that cost USD400.The balance with interest was paid in 23 monthly payments of USD16 each and a final payment of USD9.The amount of interest paid was what percent of the amount borrowed?
a.6% b.12% c.14% d.16% e.20%
Answer is d.please provide the detailed process of arithmetic.

答案

总共借款400-75=325
总共还款23*16+9=377
（377-325）/325=0.16