Answer:
C. 7 hr
Explanation:
On Friday, she ran for 16 miles at 8 Miles per hour. 16÷8=2, therefore on Friday she ran for 2 hours. On Saturday she ran for 15 miles at 7.5 Miles per hour. 15÷7,5=2, therefore on Saturday she ran for 2 hours. On Sunday she ran for 21 miles at 7 Miles per hour. 21÷7=3, therefore on Sunday she ran for 3 hours.
With a total of 2+2+3=7, we can say that Lori trained running throughout all 3 days for a total time of 7 hours. Thus the answer is C. 7 hr
Hope this helps!
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Farah Syed