Jonathan can jog 3 2/5 mile and 7/8 hour find his average speed in miles per hour

(3 2/5) / (7/8) = x / 1 ... 3 2/5 miles to 7/8 hr = x miles to 1 hr

cross multiply

(7/8) (x) = (17/5) (1) ... I turned 3 2/5 to an improper fraction 17/5

7/8x = 17/5

x = (17/5) / (7/8)

x = 17/5 * 8/7

x = 136/35 or 3 31/35 miles per hr ... or as a decimal, 3.89 miles per hr