2012年12月16日SAT数学每日一题

　　下面是一道

　　Read the following SAT test question, then click on a button to select your answer.

　　At the Cross Street Convenience Store between 11 a.m. and 1 p.m. on Friday, a total of n items were purchased. The graph above shows the distribution of the number of items purchased in each of five categories. In terms of n, how many more sandwiches than pastries were purchased?

　　A.10n

　　B.20n

　　C.

　　D.

　　E.