Question

A cuboidal steel box measured 40cm by 50 cm by 60 cm. Find the cost of the steel required for making 10 such boxes if 1 m2 of a steel sheet costs 50.​

Answer 1

Given :-

• Length of cuboid = 40 cm = 0.4 m
• breadth of cuboid = 50 cm = 0.5 m
• height of cuboid = 60 cm = 0.6 m
• rate of steel = Rs.50 per m²

To Find :-

• Cost of the steel required for making 10 cuboidal boxes?

Solution :-

we know that,

$\boxed{ \bold{T.S.A \: of \: cuboid = 2 (lb + bh + hl)}}$

$\bold{: \implies 2(0.4 \times 0.5 \: + 0.5 \times 0.6 + 0.6 \times 0.4) } \\ \\ \bold{: \implies 2(0.2 + 0.3 + 0.24)} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ \bold{: \implies 2 \times 0.74 } \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ \bold{: \implies 1.48 \: {m}^{2} } \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$

so, total surface area of one box is 1.48 m²

then,

area of required steel for 10 boxes = 10 × 1.48

➪ 14.8 m²

then,

• cost of required steel = 14.8 × 50 = 740

hence, cost of required steel is Rs. 740