PSLE
Min bought some chocolate bars and gave half of it to Gabriel. Gabriel bought some jelly beans and gave half of it to Min. Min ate 3 jelly beans and Gabriel ate 2 chocolate bars. The ratio of Min's jelly beans to chocolate bars became 1 : 4 and the ratio of Gabriel's jelly beans to chocolate bars became 1 : 2. How many jelly beans did Gabriel buy?

	Min		Gabriel
	Jelly beans	Chocolate bars	Jelly beans	Chocolate bars
Before	1 u + 3	4 u	1 p	2 p + 2
Change	- 3			- 2
After	1 u	4 u	1 p	2 p

After Min gave half of the chocolate bars to Gabriel and Gabriel gave half of his jelly beans to Min, Gabriel and Min had same number of jelly beans and chocolate bars before each ate some.

4 u = 2 p + 2 
4 u - 2 = 2 p --- (1)

1 u + 3 = 1 p --- (2)

Make p the same.

(2)_x2
2 u + 6 = 2 p --- (3)

(1) = (3)
4 u - 2 = 2 u + 6 
4 u - 2 u = 6 + 2
2 u = 8

1 u = 8 ÷ 2 = 4

1 p
= 1 u + 3
= 4 + 3
= 7

Number of jelly beans that Gabriel bought
= 2 p
= 2 x 7
= 14

Answer(s): 14