Question

An open tin box, 21 cm long, 9 cm wide, 8 cm high, is fitted with a thin lid which overlaps to a depth of 1 cm all round. What is the total area of tin sheeting used for the box and the lid?

Answer 1

Answer on Question #43985, Math, Geometry

An open tin box, 21 cm long, 9 cm wide, 8 cm high, is fitted with a thin lid which overlaps to a depth of 1 cm all round. What is the total area of tin sheeting used for the box and the lid?

Solution:

Box is open so only base add to total area

Calculate square of base: $(21*9) = 189~\mathrm{cm}^2$

Then each size of base multiply on height $(21 + 21 + 9 + 9)*8 = 480~\mathrm{cm}^2$

The area for the open box is base+square of each size $= 189 + 480 = 669~\mathrm{cm}^2$

Use the same strategy for lid:

The area for the lid will be $(21 + 21 + 9 + 9)*1 + (21*9) = 249~\mathrm{cm}^2$

Total area $= 918~\mathrm{cm}^2$