Question

The dimensions of an oil tin are $5$ cm $\times 5$ cm $\times 25$ cm. Find the area for making $20$ such tins. If $1$ sq.m sheet costs Rs. $10$, find total cost for making $20$ such tins.

• A. Rs. $18$
• B. Rs. $15$
• C. Rs. $11$
• D. Rs. $17$

Answer 1

The correct option is C Rs. $11$

By looking at the dimensions, we can say that the oil tin is in the form of a cuboid.

Total surface area of the tin $=2(lb+bh+lh)$

$=2(5\times 5+5\times 25+25\times 5)$

$=2(25+125+125)$

$=550c{m}^2$

$\therefore$ for 20 tins, area required $=550\times 20$

$=11000c{m}^2$

$=1.1m^2$

Cost of $1m^2$ tin sheet $=$ Rs. $10$

$\therefore$ cost of $1.1m^2$ tin sheet $=1.1\times 10=$ Rs. $11$