The area of a circle is 38.5cm2. Find its diameter [take \(\pi = \frac{22}{7}\)]
A
22cm
B
14cm
C
7cm
D
6cm
Verified Correct Answer: C.
Step-by-Step Mathematical Solution
\(\pi r^2\) = 38.5
\(\frac{22}{7} r^2\) = 38.5
r\(^2\) = \(\frac{38.5 \times 7}{22}\)
r = \(\sqrt{12.25}\) = 3.5
diameter = 2r = 2 x 3.5 = 7cm
Source: WAEC / JAMB / NECO Classroom Archive (Record #26468)