The pie chart above shows the statistical distribution of 80 students in five subjects in an examination. Calculate how many student offer Mathematics.
Attached Figure / Diagram
A
30
B
11
C
50
D
20
Verified Correct Answer: B.
Step-by-Step Mathematical Solution
5x^\circ + (16x - 24)^\circ + 5x^\circ + (4x + 12)^\circ + (6x + 12)^\circ = 360^\circ
36x^\circ - 24 + 12 + 12 = 360^\circ
36x^\circ = 360^\circ
x^\circ = \(\frac{360^\circ}{36}\)
= 10^\circ
Thus, the angle of sector representing Mathematics is 5 x 10^\circ = 50^\circ. Hence the number of students who offer mathematics is
\(\frac{50}{360} \times 80 \approx 11\)
Source: Myschool Past Questions Archive (Record #33155)