Cathy had some yellow stickers and blue stickers in 2 packets. In Packet K, the ratio of the number of yellow stickers to blue stickers was 8 : 5. In Packet L, the number of yellow stickers was 2 times the number of blue stickers. Cathy transferred ⁴₅ of the blue stickers from Packet K to Packet L. The number of stickers in Packet K became 108 and the ratio of the number of yellow stickers to blue stickers in Packet L became 4 : 5.

1. How many blue stickers were transferred from Packet K to Packet L?
2. What was the number of stickers in Packet L after the transfer?

	Packet K		Packet L
	Yellow	Blue	Yellow	Blue
Comparing yellow stickers and blue stickers at first	8 u	5 u	2x2 = 4 p	1x2 = 2 p
Before		5 u
Change		- 4 u		+ 4 u
After		1 u
Comparing yellow stickers and blue stickers in the end	8 u	1 u	4 p	5 p

(a)
Total number of stickers in the end for Packet K
= 8 u + 1 u
= 9 u

9 u = 108

1 u = 108 ÷ 9 = 12

Number of blue stickers that were transferred from Packet K to Packet L
= 4 u
= 4 x 12
= 48

(b)
The number of yellow stickers in Packet L remains unchanged.  Make the number of yellow stickers in Packet L the same.  LCM of 2 and 4 is 4. 

Increase in the number of blue stickers in Packet L
= 5 p - 2 p
= 3 p

3 p = 4 u
3 p = 48

1 p = 48 ÷ 3 = 16

Number of stickers in Packet L in the end
= 4 p + 5 p
= 9 p
= 9 x 16
= 144

Answer(s): (a) 48; (b) 144