The dimension of a rectangular tank are 2m by 7m by 11m. If its volume is equal to that of a cylindrical tank of height 4cm, calculate the base radius of the cylindrical tank. [Take \(\pi = \frac{22}{7}\)]
A
14cm
B
7m
C
3\(\frac{1}{2}\)m
D
1\(\frac{3}{4}\)m
Verified Correct Answer: C.
Step-by-Step Mathematical Solution
Volume of rectangular tank = L x B x H
= 2 x 7 x 11
= 154cm3
volume of cylindrical tank = \(\pi r^2h\)
154 = \(\frac{22}{7} \times r^2 \times 4\)
r2 = \(\frac{154 \times 7}{22 \times 4}\)
= \(\frac{49}{4}\)
r = \(\sqrt{\frac{49}{4}} = \frac{7}{2}\)
= 3\(\frac{1}{2}\)m
Source: Myschool Past Questions Archive (Record #45741)