Question

michael is headed to his aunts house. for the first 2 hours he drives at 55 mph. for the next hour, he drives 70 mph. for the final 2 hours he drives 50 mph. how far does he travel? what is his average speed of the entire trip? if he drives the entire trip at 70 mph, how much less time will it take?

Answer 1

Explanation:

Driving 55mph for two hours, he would travel 110 miles

Driving 70mph for one hour, he would travel 70 miles.

Driving 50mph for two hours, he would travel 100 miles.

Total Distance would be 280 miles.

Average speed would be (55+70+50)/3 = 58mph

If he drove 280 miles at 70mph, it would take 4 hours

Distance = Rate X Time

Answer 2

total distance = 280 miles

average speed = 56 mph

It will take 1 hour less.

Explanation:

distance = speed * time

First 2 hours:

distance1 = 55 mph * 2 hours = 110 miles

Next hour:

distance2 = 70 mph * 1 hour = 70 miles

Final 2 hours:

distance3 = 50 mph * 2 = 100 mph

Add the three distances:

total distance = distance1 + distance2 + distance3

= 110 miles + 70 miles + 100 miles

total distance = 280 miles

Total driving time: 2 hours + 1 hours + 2 hours = 5 hours

average speed = distance/time

average speed = 280 miles / 5 hours

average speed = 56 mph

time = distance/speed

time = 280 miles / 70 mph

time = 4 hours

difference in time = 5 hours - 1 hour = 1 hour

It will take 1 hour less.