Question

a vehicle moving at a constant speed travels 45 miles in 3/4 hour. the driver thinks he will be late to a meeting that is still 65 miles away and starts in 1.25 hours. assume he maintains a constant speed. find the drivers unit rate of speed and explain wether he was late or not.

Answer 1

1) we calculte the driver´s unit rate of speed.
s=speed
d=distance
t=time.

s=d/t


45 miles------------------3/4 hour
x----------------------------- 1 hour

x=(45 miles * 1 hour) / (3/4 hour)=60 miles.

speed or rate=60 miles / 1 hour.

2)we calculate the distance traveled at 1.25 hour.

distance=rate * time

distance=(60 miles /1 hour) * 1.25 hour=75 miles.

Answer: the driver would´t go late, because, the distance is 65 miles, and he can travel 75 miles if he drive with that speed .