# Find the least number which must be added to each of the following numbers so as to get a perfect square. Also find the square root of the perfect square so obtained.

(i) 525 (ii) 1750 (iii) 252 (iv) 1825 (v) 6412

**Solution:**

What is known: Numbers that are not perfect squares

What is unknown: What must be added from the numbers so as to get a perfect square

Reasoning: First find out the square root of the number, then round it off to the next whole number. That number is the next possible perfect square root. So we add the difference between the two to get the perfect square.

Steps:

(i)

The square root of 525 is calculated as

It is evident that 22^{2} < 525

The next perfect square of a whole number is

23^{2} = 529

Hence, the number to be added to 529

= 529 - 525

= 4

The required perfect square is 525 + 4 = 529 whose root is 23

(ii)

The square root of 1750 is calculated as

This shows that 41^{2} < 1750

Next perfect square is 42^{2} = 1764

Hence number to be added to 1750

= 1764 - 1750

= 14

The required perfect square is 1750 + 14 = 1764 whose root is 42

(iii)

The square root of 252 is calculated as

This shows that 15^{2} < 252

Next perfect square is 16^{2} = 256

Hence number to be added to 252

= 256 - 252

= 4

The required perfect square is 252 + 4 = 256 whose root is 16

(iv)

The square root of 1825 is calculated as

This shows that 42^{2} < 1825

Next perfect square is 43^{2} = 1849

Hence number to be added to 1825

= 43^{2} - 1825

= 1849 - 1825

= 24

The required perfect square is 1825 + 24 = 1849 whose root is 43

(v)

The square root of 6412 is calculated as

This shows that 80^{2} < 6412

Next perfect square is 81^{2} = 6561

Hence number to be added to 6412 is

= 6561 - 6412

= 149

The required perfect square is 6412 + 149 = 6561 whose root is 81

**Video Solution:**

## Find the least number which must be added to each of the following numbers so as to get a perfect square. Also find the square root of the perfect square so obtained. (i) 525 (ii) 1750 (iii) 252 (iv) 1825 (v) 6412

### NCERT Solutions for Class 8 Maths - Chapter 6 Exercise 6.4 Question 5

Find the least number which must be added to each of the following numbers so as to get a perfect square. Also find the square root of the perfect square so obtained. (i) 525 (ii) 1750 (iii) 252 (iv) 1825 (v) 6412

The least numbers that need to be added to the given numbers to get a perfect square are (i) 4, (ii) 14, (iii) 4, (iv) 24, and (v) 149