Question

"Question 2 Without doing any calculation, find the numbers which are surely not perfect squares. (i) 153 (ii) 257 (iii) 408 (iv) 441

Class 8 Squares and Square Roots Page 102"

Answer 1

the answers will be. a b and c as only 441 is a perfect square of 21

Answer 2

If the units digit of a number is 2, 3, 7 or 8 then it is not a perfect square and hence does not have a square root.

 

If a number has a square root then its units digit must be 0, 1, 4, 5, 6 or 9.

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Solution:

(i)153           (ii) 257           (iii) 408 are not perfect squares

Since, (i), (ii) and (iii) are surely not be perfect square as these numbers end with 3, 7 and 8.

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Hope this will help you....