PSLE
School camp shirts were available in 4 colours: silver, green, black and yellow. At the camp, each students chose one shirt. The pie chart represents the students' choice of shirt colours. 41 students chose yellow shirts. The students' choice of shirt colours is also represented by the bar graph. The bar that shows the number of students who chose silver shirts has not been drawn. How many students chose silver shirts?

    
From the pie graph,
fraction of students who chose black or green
= ^90°_360°
= ¹₄

From the bar graph,
Number of students who chose black = Number of students who chose green = 41 

¹₄ of the pie chart = 41
⁴₄ of the pie chart = 4 x 41 = 164

Total number of students = 164

Number of students who chose silver shirts
= 164 - 41 - 41 - 41
= 41

Answer(s): 41