Three women, Shannon, Jaslyn and Jen went on a shopping spree. 90% of Shannon's spending was equal to ¹₂ of Jaslyn's spending. Jen's spending was  25% less than Jaslyn's. If Jaslyn spent $720 less, she would spend the same amount of money as Jen.

1. Find the ratio of Shannon's spending to Jaslyn's to Jen's.
2. How much did Jen spend?

Shannon	Jaslyn	Jen
5x4	9x4
	4x9	3x9
20 u	36 u	27 u

(a)
90%= ⁹⁰₁₀₀ = ⁹₁₀
⁹₁₀ of Shannon's spending is equal to ¹₂ of Jaslyn's spending. Make the numerators the same.  LCM of 9 and 1 is 9.

910 of Shannon's spending = 12 of Jaslyn's spending
910 of Shannon's spending =1x92x9 of Jaslyn's spending
910 of Shannon's spending = 918 of Jaslyn's spending

Shannon : Jaslyn
10 : 18
5 : 9

Jen's spending in percent when compared to Jaslyn's
= 100% - 25%
= 75%

Jaslyn : Jen
100 : 75
4 : 3

Jaslyn's spending is the repeated identity.  Make Jaslyn's spending the same.  LCM of 9 and 4 is 36.

Shannon : Jaslyn : Jen
20 : 36 : 27

(b)

	Shannon	Jaslyn	Jen
Before	20 u	36 u	27 u
Change		- 9 u
After	20 u	27 u	27 u

Additional amount that Jaslyn would have to spend less to be the same as Jen
= 36 u - 27 u
= 9 u

9 u = 720

1 u = 720 ÷ 9 = 80

Amount that Jen spent
= 27 u
= 27 x 80
= $2160 

Answer(s): (a) 20 : 36 : 27; (b) $2160