Question 831886: Julie drives 100 mi to her Grandmother's house. On the way to Grandmother's, she drives half the distance at 40 mph and half the distance at 60 mph. On her return home, she drives half the time at 40 mph and half the time at 60 mph. A. How long does it take her to complete the trip to her Grandmother's house? B. How long does the return trip take?
Answer by JulietG(1812)   (Show Source):
You can put this solution on YOUR website! Julie is such a wonderful granddaughter!
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The total distance is 100 miles
Half this distance is 50 miles.
1/2 the distance (50 miles) is driven at 40mph.
How long will it take to drive 50 miles at 40mph?
Divide 50 by 40 to get 1.25 hours
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The second half (also 50 miles) is driven at 60 mph. How long does that take? 50 miles divided by 60 mph = 0.833 hours
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Together, it takes here 1.25 + 0.833 hours, or 2.083 hours (rounded; the 3 goes on forever).
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Now the second half of the problem.
"On her return home, she drives half the time at 40 mph and half the time at 60 mph."
If she drives half the TIME at 40 mph and half at 60 mph, how long does it take for 100 mph? 2 hours :-). 1 hour at 40, and 1 hour at 60.
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