What is the formula that you would use to find g, the amount of gas you’d have after the trip. If you start with 20 gallons of gas, have 32 miles per gallon, and drove 100 miles.

remaining gas = g
started with 20 gallons so you need to calculate amount used then subtract it from 20
amount used would be miles driven by miles per gallon so 100/32
so equation would be:
g = 20-(100/32)