Question

Two identical cubes each of total surface area of 54 cm2
are joined end to end. Find its total
surface area.

Answer 1

Answer:

We have,

Surface Area of each cube = 54cm²

Now,

Surface area = 6a²

54cm² = 6a²

54cm² = a²

6

√9 = a

1 edge of a cube = a = 3cm.

Now,

when we join two such cubes ,

Then, we will find that:

l = 6cm

b = 3cm

h = 3cm

So, Surface area of new cuboid = 2(lh + bh + lb)

SA = 2( 6*3 + 3*3 + 6*3)

SA = 2(18 + 9 + 18)

SA = 2 * 45

SA = 90cm²