Class V, W and X were given some lollipops to sell for their fund-raising project. The average number of lollipops the 3 classes had at first was 224. After Class W sold four times as many lollipops as Class V and Class X sold ⁷₈ as many lollipops as Class W, the average number of lollipops the 3 classes had left was 54. How many lollipops did Class V and Class X sell altogether?

Class V	Class W	Class X
1x2	4x2
	8x1	7x1
2 u	8 u	7 u

Class V : Class W : Class X
2 : 8 : 7

Total number of lollipops that the 3 classes had at first
= 3 x 224
= 672

Number of lollipops that the 3 classes left
= 3 x 54 
= 162

Number of lollipops that were sold by 3 classes
= 672 - 162
= 510

2 u + 8 u + 7 u = 510
17 u = 510

1 u = 510 ÷ 17 = 30

Total number of lollipops sold by Class V and Class X
= 2 u + 7 u
= 9 u
= 9 x 30
= 270

Answer(s): 270