Without doing any calculation, find the numbers which are surely not perfect squares.
(i) 153   (ii) 257   (iii) 408    (iv) 441

Solution:

The perfect square of a number has 0, 1, 2, 4, 5, 6, or 9 at the unit’s place.

(i) 153

Since the number 153 has 3 at its unit’s place, it is NOT a perfect square.

(ii) 257

Since the number 257 has 7 at its unit’s place, it is NOT a perfect square.

(iii) 408

Since the number 408 has 8 at its unit’s place, it is NOT a perfect square.

(iv) 441

Since the number 441 has 1 at its unit’s place, it is a perfect square of 21.

The numbers which are surely not perfect squares are (i) 153, (ii) 257, and (iii) 408

☛ Check: NCERT Solutions for Class 8 Maths Chapter 6

Video Solution:

Without doing any calculation, find the numbers which are surely not perfect squares. (i) 153 (ii) 257 (iii) 408 (iv) 441

NCERT Solutions for Class 8 Maths Chapter 6 Exercise 6.3 Question 2

Summary:

Without doing any calculation, the numbers which are surely not perfect squares.(i) 153, (ii) 257, (iii) 408

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