Cindy, Nora, Dana and Gabby went to buy a gift for their grandmother. They shared the cost equally among themselves. However, Gabby forgot to bring her money. So, the other 3 girls paid for the gift first. Dana paid ⁷₉ of the amount Cindy and Nora paid. Nora paid $7 more than Cindy. The next day, Gabby returned $27 to Dana and some money to Cindy and Nora. How much did Gabby return to

1. Cindy?
2. Nora?

	Cindy	Nora	Dana	Gabby	Total
Comparing the amounts 3 girls paid first	9 u		7 u		16 u
Comparing the amounts 2 girls paid first	1 p	1 p + 7
Amounts that each girl paid for Gabby first	- ?	- ?	- 27	+ 27 + ?
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 Dana paid 
= 7 u - 4 u
= 3 u

3 u = 27

1 u = 27 ÷ 3 = 9

Total amount that Cindy and Nora paid at first
= 9 u
= 9 x 9
= $81

1 p + 1 p + 7 = 81
2 p = 81 - 7
2 p = 74

1 p = 74 ÷ 2 = 37

Amount that Gabby needed to pay Cindy
= 1 p - 4 u
= 37 - 4 x 9
= 37 - 36
= $1

(b)
Amount that Gabby needed to pay Nora
= (1 p + 7) - 4 u
= (37 + 7) - 4 x 9
= 44 - 36
= $8

Answer(s): (a) $1; (b) $8