Marc P. answered • 11/03/19

Ivy League Grad to Help with Standardized Tests and Academic Work

Following the problem's hint, we find that 36 minutes = .6 hours. Now we can simply use miles for all of our distances and hours for all of our times.

This is a distance-rate problem, so we need the equation D = RT. Because there are two trips, we will need to use this equation twice.

For the first trip, we get:

D = RT

d = 445*t (letting lowercase d and t be the distance and time of the first trip)

For the second trip, we get:

D = RT

d + 239 = 555*(t - .6)

Now we substitute from the first equation into the second:

445*t + 239 = 555*(t - .6)

I'll let you solve this equation for t. (I get 5.2 hours.) The problem asks for the distance from DC to LA, which is d, so plug the value for t into the equation d = 445*t to get d = 2314 miles.