Question

How many cubes of side 15cm , 3cm and 3cm are needed to form a cube ?

Answer 1

the side of the small cube = 3cm
side of the big cube = 15cm
number of small cubes required = n
n = (volume of big cube)/(volume of small cube)

= (15 cm)³/(3cm)³


= (15*15*15)/(3*3*3)
= 5*5*5
=125

Answer 2

Answer: There are 25 cubes that are needed to form a cube.

Step-by-step explanation:

Since we have given that

Length of cubes are 15 cm, 3 cm, 3 cm.

Since we need to find the number of cubes to form a cube.

First we factorise the lengths:

$15\times 3\times 3\\\\=5\times 3\times 3\times 3\\\\\text{Since there are three 3's but only one '5', }\\\\\text{so, we need to multiply two 5's to make the complete set of 5}\\\\=5\times 5\times 5\times 3\times 3\times 3$

Hence, there are 25 cubes that are needed to form a cube.