Volume of cube formed = n × volume of one cuboid

(a)³ = n × (l×b×h)

As per the question

(a)³ = n × (5cm ×2cm ×5cm)

Now we’ve to make a perfect cube on right hand side

For that n must be equals to 5×2×2

Therefore,

n= 20

We’ll need 20 such cuboids

To form one cube.

And the volume of formed cube would be 5000cm³.