chart problem: How far away is Alton?

[santasad13]

I'm having trouble with another "chart" problem:

If Gina leaves now and drives at 66 km/h, she will reach the town of Alton just in time for her appointment. If she waits 40 minutes (to have lunch first), then she will have to go 90 km/h to get to her appointment in time. How far away is Alton?

All I can figure out is that the rates are 66 and 90.

 

[stapel]

Try creating the chart you're supposed to be using, and filling in the known information.

You are given the rates outright, so that shouldn't be too hard to fill in.

You know that she travels some time "t" at the slower rate, and 2/3 of an hour less at the faster rate. So what are your "time" expressions? Fill those in.

You know that d = rt, so create the products and fill in those slots in the chart.

You know that the distance is unchanged, so set the "distance" expressions equal. Then solve.

If you get stuck, please reply showing all of your work and reasoning. Thank you.

Eliz.