---------------------------------------------
Given information
---------------------------------------------
3 1/4 hours = 13 miles
---------------------------------------------
Find 1 hour
---------------------------------------------
1 hour = 13 ÷ 3 1/4
1 hour = 13 ÷ 13/4
1 hour = 13 x 4/13
1 hour = 4 miles
---------------------------------------------
Answer : Rate = 4 miles/hours
---------------------------------------------