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Taylor took 6 hours to drive home from college for Thanksgiving break, a total distance of 290 miles.
She was able to average 50 miles per hour for part of the trip but had to slow down to 45 miles per hour
for the rest of the time due to poor weather. How many hours did she drive at each speed?

Respuesta :

Answer: at 50 mph, she drove for 4 hours.

at 45 mph, she drove for 2 hours.

Step-by-step explanation:

Let t represent the time that she spent driving at 50 miles per hour.

Taylor took 6 hours to drive home from college for Thanksgiving break. This means that the time that she spent driving at 45 miles per hour is (6 - t) hours.

Distance = speed × time

Distance covered while driving 50 miles per hour is

50t

Distance covered while driving 45 miles per hour is

45(6 - t)

Since the total distance that she drove is 290 miles, it means that

50t + 45(6 - t) = 290

50t + 270 - 45t = 290

50t - 45t = 290 - 270

5t = 20

t = 20/5 = 4

At 45 miles per hour, she drove at

6 - 4 = 2 hours