Question

Find the total surface area of a closed cardbcardboard box of length 0.5m,breadth25cm and height 15 cm

Answer 1

$l = 0.5 \: m \\ b = 25 \: cm = 0.25 \: m \\ h = 15 \: cm = 0.15 \: m \\ total \: \: surface \: \: area \\ = 2 \times (lb + bh + lh) \\ = 2 \times (0.5 \times 0.25 + 0.25 \times 0.15 + 0.5 \times 0.15) \\ = 0.475 \: {m}^{2}$