Answer:
Step-by-step explanation:
a. Find the unit rate, or how many miles they traveled in one hour, by dividing:
[tex]\frac{392}{7}=56 mph[/tex]
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:
[tex]\frac{mi.}{hr}:\frac{56}{1}=\frac{728}{x}[/tex] and cross multiply to solve for x:
56x = 728 so
13 hours.
Now use the d = rt equation:
728 = 56t so
t = 13 hours
