Question

A closed iron tank 12 m long, 9 m wide and 4m deep is to be made. Determine the cost of iron sheet used at the rate Rs. 5 per metre sheet, sheet being 2 m wide.

Answer 1

Length $l=12m$

Breadth $b=9m$

Height $h=4m$

$\Rightarrow$ Total surface of the tank $=2(l\times b+b\times h+h\times l)$

$=2(12\times 9+9\times 4+4\times 12)$

$=2\times (108+36+48)$

$=192\times 2$

$=384m^2$

$\Rightarrow$ Length of the sheet required $=\frac{384}{2}m$

$=192m$

$\therefore$ Cost of the sheet $=192\times 5$

$=960$

$\therefore$ Total cost of the sheet $=Rs.960.$

Hence, the answer is $960.$