Answer:
10mph or 10 miles per hour
Step-by-step explanation:
From the question,
John ride 4 miles to the store and 4 miles back
Total distance travelled = 4 miles + 4 miles
= 8 miles
Total time travelled
Time to the store = 3/10 of an hour
Time back from the store = 1/2 of an hour
Total time travelled
= 3/10 + 1/2
= (3 × 2) +(10 × 1)/20
= 6 + 10/20
= 16/20
= 4/5
Total time travelled= 4/5 hour
His average rate of speed for the entire trip formula =
Speed = Total distance travelled (miles)/ Time (hour)
= 8/(4/5)hour
= 8 ÷ 4/5
= 8 × 5/4
= 40/4miles/ hour
= 10 miles/ hour
Therefore, his average rate of speed for the entire trip is 10 miles/hour