Respuesta :

Answer:

509 gallons as 815 gallons divided by 32 = 25.468 and we multiply by 20 to get 509.375 where we round down at 509 to find full gallon, anything less (via decimal) is not a full gallon.

Step-by-step explanation:

Answer:

39.15 or 39 gallons

Step-by-step explanation:

1. create an equation

815= 32+20x

2. get x by itself

783=20x

3. divide 20 to both sides of the equal sign

39.15=x

4. So Mike can buy 39.15 or 39 gallons of gas for 20$