PSLE
School camp coats were available in 4 colours: purple, red, grey and gold. At the camp, each contestants chose one coat. The pie chart represents the contestants' choice of coat colours. 33 contestants chose red coats. The contestants' choice of coat colours is also represented by the bar graph. The bar that shows the number of contestants who chose grey coats has not been drawn. How many contestants chose grey coats?

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

From the bar graph,
Number of contestants who chose purple = Number of contestants who chose gold = 54 

¹₄ of the pie chart = 54
⁴₄ of the pie chart = 4 x 54 = 216

Total number of contestants = 216

Number of contestants who chose grey coats
= 216 - 54 - 54 - 33
= 75

Answer(s): 75