Question

A plastic box $1.5m$ long, $1.25m$ wide and $65cm$ deep is to be made. It is opened at the top. Ignoring the thickness of the plastic sheet, determine the area of the sheet required for making the box?

Answer 1

It is in the from of cuboid.

But top of cuboid is open

Length of cuboid$=1.25m$

Breadth of cuboid$=1.25m$

Height of cuboid$=65cm=0.65m$

Area of sheet required $=l\times b+2\times (b\times h+h\times l)$

$=1.5\times 1.25+2\times (1.5\times 0.65+1.25\times 0.65)$

$=1.875+2\times (0.975+0.8125)$

$=5.45sq.m$