Question

10. Draw the given net, cut it out and fold it. Stick the
edges together. Write the measurements of all the
faces.
6 cm
3.5 cm
6 cm
3.5 cm
3.5 cm 2.5 cm
3.5 cm
6 cm​

Answer 1

Answer:

Two cubes each of volume 64 cm3 are joined end to end. Find the surface area of the resulting cuboid.

Sol. Volume of each cube = 64 cm3

∴ Total volume of the two cubes = 2 × 64 cm3

= 128 cm3

Let the edge of each cube = x

∴ x3 = 64 = 43

∴ x = 4 cm

Now, Length of the resulting cuboid l = 2x cm

Breadth of the resulting cuboid b = x cm

Height of the resulting cuboid h = x cm

∴ Surface area of the cuboid = 2 (lb + bh + hl) = 2[(2x . x) + (x . x) + (x . 2x)]

= 2[(2 × 4 × 4) + (4 × 4) + (4 × 2 × 4)] cm2

= 2 [32 + 16 + 32] cm2 = 2[80] cm2 = 160