On a trip to his grandparents, Donny drove 60 miles per hour for 45 minutes and 50 miles per hour for 30 minutes. How many miles did Donny drive?

Donny drove 70 miles.

Since 60 miles per hour is 1 mile a minute so for in 45 minutes he drove 45 miles. After he drove for 50 miles for thirty minutes so in totally he drove 25 since 50 divided by two is 25.