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

Correct answer is C

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