Question

Rahul makes a cuboid of plasticine of sides $5cm,2cm,5cm$. How many such cuboids will he need to form a cube?

Answer 1

Least Length of Cube $=10$

Volume of cube $={10}^3=1000$

Dimensions of cuboid $=5\times 2\times 5$

Volume of cuboid $=5\times 2\times 5=50$

So number of Cuboid required to make a cube $=\frac{1000}{50}=20$ cuboids

Thus, $20$ cuboids of dimensions $5\times 2\times 5$ are, required to make a cube.

(OR)

The dimensions of cuboid are $5\times 2\times 5$.

Since, in any cube all three dimensions are equal.

Here, the measurement of the dimension $5$ two times repeated.

So, we require one more dimension $5$.---(1)

the measurement of the dimension $2$ is only one time available.

So, we require one more dimension $2$ should repeat two times.

i.e. require $2\times 2$.---(2)

So number of Cuboid required to make a cube $=2\times 2\times 5=20$