Answer:
$4500
Explanation:
Step one:
given data
monthly earning= $600
commission =20%= 0.2
let the number of sales be x
and the total earnings be y
Hence the expression for the earnings is given as
y=0.2x+600
Step two:
Required:
the value of x. when y=$1500
1500=0.2x+600
1500-600=0.2x
900=0.2x
divide both sides by 0.2
x=900/0.2
x=4500
The minimum amount of sales need is $4500