WAEC - Mathematics (1993 - No. 16)
A cone is 14cm deep and the base radius is 4\(\frac{1}{2}\)cm. Calculate the volume of water that is exactly half the volume of the cone.[Take π = \(\frac{22}{7}\)]
49.5cm3
99cm3
148.5cm3
297cm3
445.5cm3
Explicació
Volume of a cone = \(\frac{1}{3} \pi r^2 h\)
r = 4\(\frac{1}{2}\) cm; h = 14 cm
Volume of cone = \(\frac{1}{3} \times \frac{22}{7} \times \frac{9}{2} \times \frac{9}{2} \times 14\)
= 297 cm\(^3\)
When half- filled, the volume of the water = \(\frac{297}{2} = 148.5 cm^3\)