two cyclist start from the same point at the same time and m

two cyclist start from the same point at the same time and move in opposite directions. One cyclist is traveling at 9mph, and the other cyclist is traveling
at 4mph. After 90 min, how many miles apart are the two cyclists?

Solution

S=D/T
Therefore D= S x T
For the first cyclust we have him traveling at 9mph.. and after 90mins where is he...
90 mins = 1 hour and half. or 1.5 hours.
D= 9mph x 1.5 hours
= 13.5 miles.
Second cyclist is travelling at 4mph... and after 90 mins where is he..
90 mins = 1.5 hours.
D= 4mph x 1.5 hrs
= 6 miles.
How far apart are they? We need to find the differance which is like this..
first biker-second biker= distance apart
13.5 miles-6 miles= 7.5 miles
Therefore the bikers are 7.5 miles apart or the first biker is 7.5 miles ahead of the second biker after 90 mins.
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