A cylinder has curved surface area $1320{\text{cm}}^2$ and the circumference of its base is 44 cm. Find its volume in ${\text{cm}}^3$. Take π = 22/7.

From 2π$r=44,r=(44\times 7)/44=7$ cm. The curved surface is circumference × height, so $h=1320/44=30$ cm, and the volume = $(22/7)(49)(30)=154\times 30=4620{\text{cm}}^3$. (Solving π$r=44$ gives $r=14$ cm and $18480{\text{cm}}^3$; using the cone's 1/3 gives $1540{\text{cm}}^3$; multiplying the curved surface by the whole radius, $1320\times 7=9240$, doubles the answer, since the correct link is volume = ½ × curved surface × radius.)