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Jeff recently drove to visit his parents who live 160 miles away. on his way there his average speed was 9 miles per hour faster than on his way home (he ran into some bad weather). if jeff spent a total of 8 hours driving, find the two rates.

User Dat TT
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To answer this item, we let x be Jeff's speed when going back home. With this representation, the speed from home to his parents is x + 9. The total time it took him for the trip is 8 hours. The time of each trip can be calculated by dividing the distance by time. Such concept is presented below.

8 hours = 160/x + 160/(x + 9)

The value of x from the equation is 36. Thus, his speeds were 36 miles/h and 45 miles/h.
User Mandeep Kumar
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