You and a friend each drive 50.0 km. You travel at 90.0 km/h; your friend travels at 95.0 km/h. How long will your friend have to wait for you at the end of the trip?

1.08 hours

Explanation:

Distance = speed × time

Time = distance / speed

The time you spend driving is:

t = 50.0 km / (90.0 km/hr)

t = 0.555 hr

The time your friend spends driving is:

t = 50.0 km / (95.0 km/hr)

t = 0.526 hr

The total time is 0.555 hr + 0.526 hr = 1.08 hr.

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