PSLE
School camp windbreakers were available in 4 colours: white, gold, red and silver. At the camp, each pupils chose one windbreaker. The pie chart represents the pupils' choice of windbreaker colours. 38 pupils chose silver windbreakers. The pupils' choice of windbreaker colours is also represented by the bar graph. The bar that shows the number of pupils who chose white windbreakers has not been drawn. How many pupils chose white windbreakers?

    
From the pie graph,
fraction of pupils who chose red or gold
= ^90°_360°
= ¹₄

From the bar graph,
Number of pupils who chose red = Number of pupils who chose gold = 45 

¹₄ of the pie chart = 45
⁴₄ of the pie chart = 4 x 45 = 180

Total number of pupils = 180

Number of pupils who chose white windbreakers
= 180 - 45 - 45 - 38
= 52

Answer(s): 52