Sam, Oliver and Carl had some stickers in the ratio of 2 : 3 : 5. Carl gave 40% of his stickers to Sam and Oliver. As a result, Sam had the same number of stickers as Oliver and Carl had 43 fewer stickers than Sam.

1. What was the percentage increase in Sam's stickers after receiving from Carl?
2. How many stickers did Oliver have at first?

Sam	Oliver	Carl	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 Carl gave away
= 40% x 5
= ⁴⁰₁₀₀ x 5
= 2 u

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

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

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

(b)
3.5 u = 3 u + 43
3.5 u - 3 u = 43
0.5 u = 43

1 u = 43 ÷ 0.5 = 86

Number of stickers that Oliver had at first
= 3 u
= 3 x 86
= 258

Answer(s): (a) 75%; (b) 258