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Samantha drove a total of 641.5 miles in two legs of a trip.
In the first part of her trip, she drove at a constant speed for 5.5 hours.
In the second part of her trip, she drove 10 miles per hour slower,
and drove for 6 hours. How fast was Samantha driving in each leg of the trip?
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Let x be her rate in the first part of the trip, in miles per hour.
Then in the second part of the trip, her rate was (x-10) mph.
Write the total distance equation
5.5x + 6*(x-10) = 641.5 miles.
Solve this equiation to find x
5.5x + 6x - 60 = 641.5
5.5x + 6x = 641.5 + 60
11.5x = 701.5
x = = 61.
ANSWER. Her rate was 61 mph in the first part and 61-10 = 51 mph in the second part.
Solved.