Ahmad, Jenson and Simon had some stickers in the ratio of 3 : 4 : 7. Simon gave 50% of his stickers to Ahmad and Jenson. As a result, Ahmad had the same number of stickers as Jenson and Simon had 49 fewer stickers than Ahmad.

1. What was the percentage increase in Ahmad's stickers after receiving from Simon?
2. How many stickers did Jenson have at first?

Ahmad	Jenson	Simon	Total
3 u	4 u	7 u	14 u
+ 3.5 u		- 3.5 u
5.25 u	5.25 u	3.5 u	14 u

(a)
Number of stickers that Simon gave away
= 50% x 7
= ⁵⁰₁₀₀ x 7
= 3.5 u

Number of stickers that Ahmad and Jenson each had in the end
= (14 u - 3.5 u) ÷ 2
= 10.5 u ÷ 2
= 5.25 u

Increase in the number of stickers that Ahmad had
= 5.25 u - 3 u
= 2.25 u

Percentage increase in Ahmad's stickers after receiving from Simon
= ^2.25₃ x 100%
= 75%

(b)
5.25 u = 3.5 u + 49
5.25 u - 3.5 u = 49
1.75 u = 49

1 u = 49 ÷ 1.75 = 28

Number of stickers that Jenson had at first
= 4 u
= 4 x 28
= 112

Answer(s): (a) 75%; (b) 112