# What is the Smallest Number by Which the Following Number Must Be Multiplied, So that the Products is Perfect Cube? 107811 - Mathematics

Sum

What is the smallest number by which the following number must be multiplied, so that the products is perfect cube?

107811

#### Solution

On factorising 107811 into prime factors, we get:

$107811 = 3 \times 3 \times 3 \times 3 \times 11 \times 11 \times 11$

On grouping the factors in triples of equal factors, we get:

$107811 = \left\{ 3 \times 3 \times 3 \right\} \times 3 \times \left\{ 11 \times 11 \times 11 \right\}$
It is evident that the prime factors of 107811 cannot be grouped into triples of equal factors such that no factor is left over. Therefore, 107811 is a not perfect cube. However, if the number is multiplied by  $3 \times 3 = 9$, the factors be grouped into triples of equal factors such that no factor is left over.
Thus, 107811 should be multiplied by 9 to make it a perfect cube.

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#### APPEARS IN

RD Sharma Class 8 Maths
Chapter 4 Cubes and Cube Roots
Exercise 4.1 | Q 11.5 | Page 8