Question

Julie wrote the rate $108 in 6 weeks as a unit rate. Find her mistake and correct it.

Answer 1

Julie wants to express $108 in 6 weeks as a unit rate.

Her errors are:
$108 = $54   (Not true)
6 weeks = 3 weeks (Not true).

Instead,
$\frac{\ 108}{6\,weeks} \\ = \frac{\ 54 \times 2}{3\,weeks \times 2} \\ = \frac{\ 54}{3\,weeks} \\ =18 \, \frac{\ }{week}$

The correct unit rate is 18 $/week.