Liz earned *d* dollars for *h* hours of babysitting. At that rate, how much will she earn in *x* hours? Write a formula that works. Then use numbers to check it: Make up a reasonable hourly rate for babysitting, assume she sits for 3 hours (that’s *h*), and get her total (that’s *d*). Now figure out what she’d get for 5 hours (that’s *x*) and see if your formula works.

Liz earned *d* dollars for *h* hours. Thus, her hourly rate is *d*/*h*.

In *x* hours she will earn *xd*/*h* dollars.

If she earned $28.50 for 3 hours, 28.5/3 = $9.50 per hour.

So tonight she’ll earn 5 x 9.50 = $47.50.