PSLE
The pie charts show the number of each type of stationery in 2 stationery boxes, H and J. The total number of stationery in Box H is four times the total number of stationery in Box J.

1. Find the percentage of pens in Box H.
2. What fraction of stationery in Box J is pens?
3. The number of pens in Box H is 240. Find the number of pens in Box J.

(a)
^90°_360° = 25% of stationery in Box H

Percentage of staplers in Box H = 25%

Percentage of pens in Box H
= 100% - 45% - 25%
= 30%

(b)
Percentage of pens in Box J
= 100% - 65% - 25%
= 10%

Fraction of stationery in Box J that is pens
= ¹₁₀

(c)
30% of stationery in Box H = 240
1% of stationery in Box H = 240 ÷ 30 = 8 
100% of the stationery in Box H = 100 x 8 = 800

Number of stationery in Box J
= 800 ÷ 4
= 200

100% of stationery in Box J = 200
1% of stationery in Box H = 200 ÷ 100 = 2
10% of stationery in Box H = 10 x 2 = 20  

Number of pens in Box J = 20

Answer(s): (a) 30%; (b) ¹₁₀; (c) 20