translate to an equation F $ 0.30 folders and N $1.50 totals $12

Question

can you determine 3 different combination of folders and notebooks that total $12

Answer 1

.30F + 1.5N = 12

The N's cost 5 times as much as the F's.

So, for each extra 5 F's you need 1 less N.

F N Total (.3F + 1.5N)
0 8 12
5 7 12
10 6 12
...
40 0 12