GMAT Test Prep: DS-63153470 GMAT Data Sufficiency

On a recent trip, Mary drove 50 miles. What was the average speed at which she drove the 50 miles?

(1) She drove 30 miles at an average speed of 60 miles per hour and then drove the remaining 20 miles at an average speed of 50 miles per hour.

(2) She drove a total of 54 minutes.
Select one of the following answer choices