Question

Sara worked 22 hours last week. Joan worked for hours less than Sara, and Erin worked half as many hours as Joan. How many hours did Sara, Joan, and Erin work last week?

Answer 1

Sara - 22
Joan = Sara - 4 = 18
Erin = Joan / 2 = 9

Answer 2

Let

x------> the number of hours Sara worked last week

y------> the number of hours Joan worked last week

z------> the number of hours Erin worked last week

we know that

$x=22\ hours$ -------> equation $1$

$y=x-4$ -------> equation $2$

substitute the value of x in the equation $2$

$y=22-4$

$y=18\ hours$

$z=\frac{y}{2}$ -------> equation $3$

substitute the value of y in the equation $3$

$z=\frac{18}{2}$

$z=9\ hours$

therefore

the answer is

Sara worked $22\ hours$

Joan worked $18\ hours$

Erin worked $9\ hours$