Question

Find the volume of the cylinder whose total surface area is 1628 $c{m}^2$ and the circumference of its cross-section is 44 cm.

• A. 4520
• B. 4620
• C. 5240
• D. none of the above

Answer 1

The correct option is B 4620

cylinder's total surface area = 1628 sq.cm
$2\pi \ast r^2+2\pi \ast r\ast h=1628$
circumference of its cross-section is 44 cm
$2\pi \ast r=44$
$r=7$
So,
$2\pi \ast r^2+2\pi \ast r\ast h=1628$
$2\pi \ast 7^2+2\pi \ast 7\ast h=1628$
$h=30$
the volume of the cylinder
$V=\pi r^{2}h$
$V=\pi \ast 7^2\ast 30$
$V=4620$