You are given a math word problem and you are supposed to apply multiplication or division mathematical operators on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

Each chocolate bar in a box cost $ 4 . If a box had 11 bars total and Vanessa sold all but 7 bars , how much money would she have made ?
16

Isabel had 2 pages of math homework and 4 pages of reading homework . If each page had 5 problems on it , how many problems did she have to complete total ?
30

Mary , Sam , Keith , and Alyssa each have 6 baseball cards . How many baseball cards do they have in all ?

24