Question

find total surface area and lateral surface area of the cube whose side is 1) 8m 2) 21 cm 3) 7.5 cm​

Answer 1

Given that

1)8m 2)21cm 3)7.5cm

To calculate

Total surface area of cube

Lateral surface area of cube

Solution

Let

tsa as total surface area of cube

lsa as lateral surface area of cube

a as side of cube

As we know that

$total \: surface \: area \: of \: cube = 6 \times {a}^{2}$

$lateral \: surface \:area \: of \: cube = 4 \times {a}^{2}$

hence

1)8m

as a is 8m then

$tsa = 6 \times {a}^{2} \\ = 6 \times {8}^{2} \\ = 384 {m}^{2}$

$lsa = 4 \times {a}^{2} \\ = 4 \times {8}^{2} \\ = 256 {m}^{2}$

2)21cm

$tsa = 6 \times (21 {)}^{2} \\ = 2646 {cm}^{2}$

$lsa = 4 \times {21}^{2} \\ = 1764 {cm}^{2}$

3)7.5cm

$tsa = 6 \times {7.5}^{2} \\ = 337.5 {cm}^{2}$

$lsa = 4 \times {7.5}^{2} \\ = 225 {cm}^{2}$