Answer:
18 minutes
Step-by-step explanation:
the formula for speed is distance/time, but we're trying to find the amount of time.
If you multiply both sides by time, you get (speed)(time)=distance.
divide by speed on both sides.
Time=distance/speed.
now that we have the correct formula, substitute the values.
60 miles/50 mph = 1.2 hours.
we need how many minutes though, so we multiply 1.2 by 60.
that's 72 minutes. he expected to reach in 72 minutes.
now do that for the actual speed, and you get
60 miles/40 mph = 1.5 hours.
multiply by 60 again.
That's 90 minutes. he actually reached in 90 minutes.
to find how many more minutes it took, simply subtract the actual amount of time by the expected amount of time. 90-72=18 minutes.
