Nicole and Gillian used the same number of chocolate chips to bake cakes. Nicole used ⁵₇ of her chocolate chips and Gillian used ³₄ of her chocolate chips. They had a total of 123 chocolate chips at first.

1. How many chocolate chips did each girl use?
2. How many chocolate chips did both girls have left altogether?

	Nicole	Gillian	Total
Before	7x3 = 21 u	4x5 = 20 u	41 u
Change	- 5x3 = - 15 u	- 3x5 = - 15 u
After	2x3 = 6 u	1x5 = 5 u	11 u

(a)
Nicole and Gillian used the same number of chocolate chips to bake cakes.  Make the numerators the same. LCM of 5 and 3 is 15. 
5x37x3 of Mary's chocolate chips = 3x54x5 of Gillian's chocolate chips 
1521 of Mary's chocolate chips = 1520 of Gillian's chocolate chips 

Total number of chocolate chips at first
= 21 u + 20 u
= 41 u

41 u = 123

1 u = 123 ÷ 41 = 3

Number of chocolate chips that each girl used
= 15 u
= 15 x 3
= 45 

(b)
Total number of chocolate chips that both girls had left 
= 6 u + 5 u
= 11 u
= 11 x 3
= 33

Answer(s): (a) 45; (b) 33