Mathematics 65 Online
OpenStudy (anonymous):

the distance between 2 cites is 90miles away,and a woman drives from 1 city to another at the rateof 45 mph.at what rate must she return

OpenStudy (anonymous):

if the total travel time is 3 hours and 40 min

So first things first, we know the two cities are 90 miles away from each other, and we know she drove in one direction at 45mph. 45 miles per hour means that in one hour, she crosses 45 miles. $\frac{1\text{ hour}}{45\text{ miles}} \cdot 90\text{ miles} = 2\text{ hours}$ So the first part of her trip happens in 2 hours, since at 45 mph it takes 2 hours to cross 90 miles.

Now the next part is the question of what rate she has when she returns. We can figure that out by seeing how much time she has left: if she travels from 3 hours and 40 minutes total, and she took 2 hours to go one way, she has 1 hour and 40 minutes left to go back.

OpenStudy (tim):

Kristen, what grade are you in? How did you find out about OpenStudy?

OpenStudy (anonymous):

11th grade i seen it online

So we need to find out how fast she needs to be going to go 90 miles in 1 hour and 40 minutes. Can you figure that out?

OpenStudy (tim):

ah, okay. Have you ever paid for online tutoring?

OpenStudy (anonymous):

no i havent

OpenStudy (tim):

cool, thx, just wondering...would you ever pay for it?

OpenStudy (anonymous):

why?

OpenStudy (tim):

just wondering. I'm think about starting an online tutoring company :)

OpenStudy (anonymous):

oh well i might one day:)

OpenStudy (tim):

gotcha, thanks! Would you rather pay per question or would you rather pay to have access to something like this?

OpenStudy (anonymous):

i would rather pay 2 somthing like this not per question thats just crazy lol