Question

NEED HELP PLZ!!!!!!George and John travel 392 miles in 7 hours. If they travel at the same rate, how long will it take them to travel 728 miles?

a) Find their rate: _____ mph


b) It took them ____ hours to travel 728 miles

Answer 1

Explanation:

a. Find the unit rate, or how many miles they traveled in one hour, by dividing:

`(392)/(7)=56 mph`

b. Now that we know how fast they were going, we can use it in either a proportion or in the d = rt equation. For the proportion set up, put miles on the top and hours on the bottom and solve for the unknown:

`(mi.)/(hr):(56)/(1)=(728)/(x)` and cross multiply to solve for x:

56x = 728 so

13 hours.

Now use the d = rt equation:

728 = 56t so

t = 13 hours