Question

How many quarts is 2.5 gallons

Answer 1

2.5 gallons 
how many quarts?

1 gallon = 4 quarts

Make proportions:
$\frac{1}{4}$ = $\frac{2.5}{q}$
2.5 × 4 = 1q
10 quarts = q

2.5 gallons = 10 quarts

Answer 2

The answer would be: 10 quarts