PSLE
School camp windbreakers were available in 4 colours: blue, brown, black and pink. At the camp, each contestants chose one windbreaker. The pie chart represents the contestants' choice of windbreaker colours. 37 contestants chose brown windbreakers. The contestants' choice of windbreaker colours is also represented by the bar graph. The bar that shows the number of contestants who chose black windbreakers has not been drawn. How many contestants chose black windbreakers?

    
From the pie graph,
fraction of contestants who chose blue or pink
= ^90°_360°
= ¹₄

From the bar graph,
Number of contestants who chose blue = Number of contestants who chose pink = 45 

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

Total number of contestants = 180

Number of contestants who chose black windbreakers
= 180 - 45 - 45 - 37
= 53

Answer(s): 53