Justin, Jeremy and Brandon had some cards in the ratio of 2 : 3 : 5. Brandon gave 40% of his cards to Justin and Jeremy. As a result, Justin had the same number of cards as Jeremy and Brandon had 40 fewer cards than Justin.

1. What was the percentage increase in Justin's cards after receiving from Brandon?
2. How many cards did Jeremy have at first?

Justin	Jeremy	Brandon	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 cards that Brandon gave away
= 40% x 5
= ⁴⁰₁₀₀ x 5
= 2 u

Number of cards that Justin and Jeremy each had in the end
= (10 u - 3 u) ÷ 2
= 7 u ÷ 2
= 3.5 u

Increase in the number of cards that Justin had
= 3.5 u - 2 u
= 1.5 u

Percentage increase in Justin's cards after receiving from Brandon
= ^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 cards that Jeremy had at first
= 3 u
= 3 x 80
= 240

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