PSLE
The pie charts show the number of each type of stationery in 2 stationery boxes, N and P. The total number of stationery in Box N is thrice the total number of stationery in Box P.

1. Find the percentage of pens in Box N.
2. What fraction of stationery in Box P is pens?
3. The number of pens in Box N is 180. Find the number of pens in Box P.

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

Percentage of files in Box N = 25%

Percentage of pens in Box N
= 100% - 55% - 25%
= 20%

(b)
Percentage of pens in Box P
= 100% - 50% - 25%
= 25%

Fraction of stationery in Box P that is pens
= ¹₄

(c)
20% of stationery in Box N = 180
1% of stationery in Box N = 180 ÷ 20 = 9 
100% of the stationery in Box N = 100 x 9 = 900

Number of stationery in Box P
= 900 ÷ 3
= 300

100% of stationery in Box P = 300
1% of stationery in Box N = 300 ÷ 100 = 3
25% of stationery in Box N = 25 x 3 = 75  

Number of pens in Box P = 75

Answer(s): (a) 20%; (b) ¹₄; (c) 75