PSLE
School camp skirts were available in 4 colours: white, grey, purple and yellow. At the camp, each kids chose one skirt. The pie chart represents the kids' choice of skirt colours. 40 kids chose white skirts. The kids' choice of skirt colours is also represented by the bar graph. The bar that shows the number of kids who chose grey skirts has not been drawn. How many kids chose grey skirts?

    
From the pie graph,
fraction of kids who chose purple or yellow
= ^90°_360°
= ¹₄

From the bar graph,
Number of kids who chose purple = Number of kids who chose yellow = 60 

¹₄ of the pie chart = 60
⁴₄ of the pie chart = 4 x 60 = 240

Total number of kids = 240

Number of kids who chose grey skirts
= 240 - 60 - 60 - 40
= 80

Answer(s): 80