Question

Question 123

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Answer 1

To find the total surface area, we draw the figure as given below.

$\therefore$ Upper surface area
$=18\times 3+8\times 18+5\times 18=54+144+90=288c{m}^2$
$\therefore$ Lower surface area $=288c{m}^2$
$\therefore$ Surface area of those faces which are flat from right
$=18\times 18+2\times 18+3\times 18=324+36+54=414c{m}^2$
Also, surface area of that face which are flat from left
$=414c{m}^2$
Surface area of front face
$=18\times 5+2\times 8+8\times 18+3\times 2+3\times 18+3\times 3=90+16+144+6+54+9=319c{m}^2$
Surface area of the back face $=319c{m}^2$
$\therefore$ Total surface area
$=288+288+414+414+319+319=288+1754=2042c{m}^2$