Cody, Tommy and Will had some stickers in the ratio of 2 : 3 : 5. Will gave 40% of his stickers to Cody and Tommy. As a result, Cody had the same number of stickers as Tommy and Will had 40 fewer stickers than Cody.

1. What was the percentage increase in Cody's stickers after receiving from Will?
2. How many stickers did Tommy have at first?

Cody	Tommy	Will	Total
2 u	3 u	5 u	10 u
+ 2 u		- 2 u
3.5 u	3.5 u	3 u	10 u

(a)
Number of stickers that Will gave away
= 40% x 5
= ⁴⁰₁₀₀ x 5
= 2 u

Number of stickers that Cody and Tommy each had in the end
= (10 u - 3 u) ÷ 2
= 7 u ÷ 2
= 3.5 u

Increase in the number of stickers that Cody had
= 3.5 u - 2 u
= 1.5 u

Percentage increase in Cody's stickers after receiving from Will
= ^1.5₂ x 100%
= 75%

(b)
3.5 u = 3 u + 40
3.5 u - 3 u = 40
0.5 u = 40

1 u = 40 ÷ 0.5 = 80

Number of stickers that Tommy had at first
= 3 u
= 3 x 80
= 240

Answer(s): (a) 75%; (b) 240