The remaining trip is 20 - 5 = 15 miles long.
Mike spends = of an hour = 15 minutes for the first part of the trip;
hence, he spends 30 - 15 = 15 minutes for the remaining part.
Thus Mike moves remaining part of 15 miles in 15 minutes;
hence, his speed is 1 mile per minute, or 60 miles per hour. ANSWER
You can put this solution on YOUR website! -----------------------------------------
A car travels 20 miles in 30 minutes.
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"A car" travels at the speed of 40 miles per hour.
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If Mike drives the first 5 miles at 20 mph
How fast is he driving the remainder of the trip?
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Is Mike driving "A car"?
That car travels at 40 mph, not at 20 mph.
The description for Mike and his travel is incomplete.
Maybe your exercise description was supposed to be like this:
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Mike drives the first five miles of a 20 mile trip at 20 mph. How fast does he drive the remainder of this trip?
SPEEDS TIME in Hours MILES DISTANCE
FirstPart 20 5/20=1/4 5
Remainder 1/2-1/4=1/4 20-5=15
TOTAL 1/2 20
The missing speed for the "Remainder" of the trip is
or 60 mph.
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