I drove to my parents' house at 40 miles per hour. If I had driven 30 miles an hour instead, then I would have gotten there 20 minutes later. How many miles did I drive?

48 miles

Step-by-step explanation:

40mph =

30mph = + 20 minutes

40-30 = 10mph which means that 10mph = 20 minutes

20 x 4 = 80 minutes - this is how long it took to drive 40 miles

80 mins =  1.2 hours

40mph x 1.2 to find out distance travelled as speed x time = distance

= 48 miles

it is a. 4.2 because 7.6-3.4 gets the remaining length of 4.2. i might be wrong but i am pretty sure this is the answer.

step-by-step explanation:

your answer is a