WAEC - Mathematics (2018 - No. 21)
The total surface area of a hemispher is 75\(\pi cm^2\). Find the radius.
5.0 cm
7.0 cm
8.5 cm
12.0 cm
คำอธิบาย
Total surface area of hemisphere is
3\(\pi r^2\) = 75\(\pi cm^2\)
\(r^2\) = \(\frac{75 \pi}{3 \pi}\)
\(r^2\) = 25
r = \(\sqrt{25}\)
r = 5cm