A car traveling on Interstate 55 travels 120 miles in one and a half hours. What is the cars speed in miles per hour? *
need help

You don't need help.  You know the formula:  Distance = (speed) x (time)

The formula is always true, for any distance, speed, and time.

Plug in the numbers you know:  120 miles = (speed) x (1.5 hours)

Divide each side by "1.5 hours": (120 mi / 1.5 hr)  =  speed

Doo-da division:  120/1.5 mi/hr = speed

Clean it up:  80 miles/hour = speed

understand that i don't know the answers

will someone answer his question