Mensuration Practice Test 6

Volume of a cuboid = l × b × h = 6 × 3 × 2
= 36 cm3
Volume of a cube = (a)3 = 1 cm3
Number of cubes formed = $\frac{36}{1}$ = 36 cubes
Surface area of the cuboid = 2(lb + bh + hl)
= 2(18 + 6 + 12) = 72 $\mathit{c}{\mathit{m}}^2$
Surface area of 36 cubes = $36\left(6{\mathit{a}}^2\right)$ = 36 × 6 × 1 = 216 $\mathit{c}{\mathit{m}}^2$
Percentage increase = $\frac{216-72}{72}\times 100$
= $\frac{144}{72}\times 100$ = 200 %