PQR is a sector of a circle centre O, radius 4cm. If PQR = 30^o, find, correct to 3 significant figures, the area of sector PQR. [Take \(\pi = \frac{22}{7}\)]

4.19cm²

8.38cm²

10.5cm²

20.9cm²

Correct answer is A

Given q² = 25 - r².....(1)

from pythagora's theorem

P² = q² + r².......(2)

put (1) into (2)

p² = 25 - p² + x²

p² = 25

p = \(\sqrt{25}\)

= 5

See all Mathematics questions & answers

See more WAEC questions & answers

PQR is a sector of a circle centre O, radius 4cm. If PQR = 30o, find, correct to 3 significant figures, the area of sector PQR. [Take \(\pi = \frac{22}{7}\)]