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3 years ago

Brian drives 215 miles at an average speed. He then travels 75 more miles at a speed

Mathematics

1 answer:

Sedaia [141]3 years ago

6 0

His average speed for the first trip is 43 mph

Since Brian's average speed is x and he travels the first part for 215 miles in time t.

So, his distance d = xt

Also, the travels 75 more miles at a speed of 15 mph.

Since distance = speed time, the time he takes to cover this distance is

t' = distance/speed = 75 mi/15 mph = 5 hours

Since he covers both distances in the same time, we have that t = t' = 5 hours.

So, his average speed for the first trip x = d/t

= 215 mi/5 h

= 43 mph

His average speed for the first trip is 43 mph

Learn more about average speed here:

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