waecmaths question:
The volume of a cuboids is 54cm3, if the length, width, and height of the cuboid are in the ratio 2: 1:1. respectively. Find its total surface area
Option A:
108cm2
Option B:
90cm2
Option C:
80cm2
waecmaths solution:
$\begin{align} & V=lbh \\ & 54c{{m}^{3}}=lbh \\ & 54=2x\times x\times x \\ & 27={{x}^{3}} \\ & x=3 \\ & length=2x=2\times 3=6cm \\ & breadth=x=3cm \\ & height=3cm \\ & surface\text{ }area=2(lb+lh+bh) \\ & A=2[(6\times 3)+(6\times 3)+(3\times 3)] \\ & A=2[18+18+9]=2\times 45=90c{{m}^{2}} \\\end{align}$
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