Question

A self help group wants to manufacture jokes caps (conical shapes) of $3\text{c}m$ radius and $4cm$ height. If the available colour paper sheets is $1000\text{c}{m}^2$, then how many caps can be manufactured from that paper sheet?

Answer 1

$\Rightarrow$ We have given, $Height\left(h\right)=4cm$ and

$radius\left(r\right)=3cm$

.$\Rightarrow$ Let slant height be $l$.

We know that,

$l^2=h^2+r^2$

$l^2=(4{)}^2+(3{)}^2$

$l^2=16+9$

$l^2=25$

$\therefore$ $l=5cm$

$\Rightarrow$ Curve surface area of $1$ joker cap $=\pi rl$

$=\frac{22}{7}\times 3\times 5$

$=47.14c{m}^2$

$\Rightarrow$ Available color paper sheet $=1000c{m}^2$

$\Rightarrow$ Number of caps manufacture from $1000c{m}^2$ paper sheet $=\frac{1000}{47.14}=21.21$