If you would like to
know how many of each did Jan buy, you can calculate this
using the following two equations:
b ... the number of books
m ... the number of magazines
$16 = b * $3 + m * $2.50 ... 16 = 3 * b + 2.50 * m
b + m = 6 ... b = 6 - m
__________________
16 = 3 * b + 2.50 * m
16 = 3 * (6 - m) + 2.50 * m
16 = 3 * 6 - 3 * m + 2.50 * m
16 - 18 = - 3 * m + 2.50 * m
- 2 = - 0.50 * m /0.50
m = 2 / 0.50
m = 4 magazines
b = 6 - m = 6 - 4 = 2 books
Result: Jan bought 4 magazines and 2 books.
