9514 1404 393
Answer:
19.25 miles
Step-by-step explanation:
Antoine's rate before lunch was ...
(5.25 mi)/(3 h) = 1.75 mi/h
Then his rate after lunch was ...
2×(1.75 mi/h) = 3.5 mi/h
The distance he hiked after lunch was ...
distance = speed × time
(4 h)×(3.5 mi/h) = 14 mi
The distance Antoine hiked is the total of his before-lunch distance and his after-lunch distance:
5.25 mi + 14 mi = 19.25 mi