Answer:
Jane's friend is wrong. The original price was $50
Step-by-step explanation:
Jane got a 20% discount, so she paid 80% of the original price. As a ratio she paid
80% ÷ 100% = 80/100 = 4/5
She paid four fifths the regular price, so we can set up an equation to find out what that price was.
(4/5)x = 40 (four-fifths of some value is 40)
now solve for x
multiply both sides by 5 to get rid of the fraction..
4x = 200
divde both sides by 4 to isolate x
x = 50
$50 was the original price