It would Gretchen 192 minutes to swim the entire 2 2/5 mile course.
What is speed?
Speed is distance divided by the time taken to cover the distance.
In this case, we can determine distance covered in a minute by dividing the speed by the distance, which is distance of 7/8 mile(i.e. 0.825 mile) over the time take to cover the distance.
speed per minute=0.825/70
speed per minute=0.0125 mile/minute
With this, we can determine the time in minutes it would take to cover 2.4 miles(2/5=0.4)
0.0125=2.4/time
0.0125*time=2.4
time=2.4/0.0125
time=192 minutes
Find in the link below more about speed:
https://brainly.com/question/3004254
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