Jaslyn, Sarah, Cindy and Betty went to buy a gift for their mother. They shared the cost equally among themselves. However, Betty forgot to bring her money. So, the other 3 girls paid for the gift first. Cindy paid ⁵₁₁ of the amount Jaslyn and Sarah paid. Sarah paid $11 more than Jaslyn. The next day, Betty returned $13 to Cindy and some money to Jaslyn and Sarah. How much did Betty return to

1. Jaslyn?
2. Sarah?

	Jaslyn	Sarah	Cindy	Betty	Total
Comparing the amounts 3 girls paid first	11 u		5 u		16 u
Comparing the amounts 2 girls paid first	1 p	1 p + 11
Amounts that each girl paid for Betty first	- ?	- ?	- 13	+ 13 + ?
Comparing the amounts each girl should pay	1x4 = 4 u	1x4 = 4 u	1x4 = 4 u	1x4 = 4 u	4x4 = 16 u

(a)
The total amount that the 4 girls paid is repeated. Make the total amount the same.  LCM of 4 and 16 is 16.

Extra amount that Cindy paid 
= 5 u - 4 u
= 1 u

1 u = 13

Total amount that Jaslyn and Sarah paid at first
= 11 u
= 11 x 13
= $143

1 p + 1 p + 11 = 143
2 p = 143 - 11
2 p = 132

1 p = 132 ÷ 2 = 66

Amount that Betty needed to pay Jaslyn
= 1 p - 4 u
= 66 - 4 x 13
= 66 - 52
= $14

(b)
Amount that Betty needed to pay Sarah
= (1 p + 11) - 4 u
= (66 + 11) - 4 x 13
= 77 - 52
= $25

Answer(s): (a) $14; (b) $25