Respuesta :

Answer:

20 miles per gallon

Step-by-step explanation:

We want a unit rate where

1 is in the denominator

so we divide top and bottom by 20

[tex]\frac{400 miles/20}{20 gallons/20}[/tex]  = [tex]\frac{20 miles}{1 gallon}[/tex] = 20 miles a gallon