Jethro walked at an average speed of 3 miles per hour for 2 hours. Randy walked at an average of 4 miles per hour for 3 hours.

Which explanation correctly tells how to calculate the total number of miles the two boys walked?

A.
Step 1 Divide: 3 ÷ 2.
Step 2 Divide: 4 ÷ 3.
Step 3 Subtract the two quotients.

B.
Step 1 Divide: 3 ÷ 2.
Step 2 Divide: 4 ÷ 3.
Step 3 Add the two quotients.

C.
Step 1 Multiply: 3 × 2.
Step 2 Multiply: 4 × 3.
Step 3 Add the two products.

D.
Step 1 Multiply: 3 × 2.
Step 2 Multiply: 4 × 3.
Step 3 Subtract the two products.