Respuesta :
3 2/5 = 17 / 5 ;
(17/5) ÷ (7/8) = (17/5) × (8/7) = 136/35 = 3.88 miles per hour ;
(17/5) ÷ (7/8) = (17/5) × (8/7) = 136/35 = 3.88 miles per hour ;
(3 2/5 miles)/ (7/8 hour)= 3 31/35 miles/hour.
His average speed is 3 31/35 miles/hour~
His average speed is 3 31/35 miles/hour~