Four sisters bought a present for their mother. they received a 10% discount on the original price of the gift. after the discount was taken, each sister payed $9. what was the original price of the gift

$40

Step-by-step explanation:

x is the original price of the gift

(10% of x) is the value of the discount

(10% of x) = 10/100 . x = 0.1 x

0.1 x    is the value of the discount

x - (10% of x) is what was paid, after the discount

x - 0.1 x = 0.9 x

0.9 x    is what was paid

4 children paid $9/each

4 times $9 = $36

$36 is the total amount that was paid by the children

$36 = 0.9 x

$36 / 0.9 = x

x = $36 / 0.9 = 360 / 9

x = 40

;-)