Clifton drove for 3 hours at 52 mph. How fast must he drive during the next hour in order to have an average speed of 55 mph?

64 mph

Step-by-step explanation:

Given that:

Speed for the first 3 hours = 52 mph

Average speed for 4 hours = 55 mph

To find:

Speed for the next hour = ?

Solution:

Formula for average speed is given as:

Formula for Distance:

Distance traveled in first 3 hours:

Let the speed for the next hour = u mph

Distance traveled in 1 hour =

Total distance traveled = (156 + u) miles

Total time = 4 hours

Average Speed = 55 mph

Putting the values in formula:

So, the answer is: 64 mph

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step-by-step explanation: