PSLE
School camp vests were available in 4 colours: red, blue, silver and yellow. At the camp, each participants chose one vest. The pie chart represents the participants' choice of vest colours. 35 participants chose yellow vests. The participants' choice of vest colours is also represented by the bar graph. The bar that shows the number of participants who chose red vests has not been drawn. How many participants chose red vests?

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

From the bar graph,
Number of participants who chose silver = Number of participants who chose blue = 42 

¹₄ of the pie chart = 42
⁴₄ of the pie chart = 4 x 42 = 168

Total number of participants = 168

Number of participants who chose red vests
= 168 - 42 - 42 - 35
= 49

Answer(s): 49