9514 1404 393
Answer:
1.12 times as great
Step-by-step explanation:
The speed from Boston is ...
(210 mi)/(4 2/3 h) = 45 mi/h
Then the speed to Boston is ...
50.4/45 = 1.12 . . . times as great
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The speed on the return trip is 1.12 times as great, or 12% greater than on the trip to Sherbrooke.