Answer:
1/15 gal / mile if your numbers are correct
Step-by-step explanation:
1/5 / 15/4 = 1/5 * 4 / 15 = 4/60 = 1/15
When you know the coordinates of a point and the slope of a line, you can use the formula

in your case,
and
, so you have

Hi there! The answer is 210 pages.
We can find our answer by looking at the proportions:
20 % is 42 pages.
10 % is 21 pages (42 / 2).
100% is 210 pages. (21 × 10).