"Question 1 What could be the possible ‘one’s’ digits of the square root of each of the following numbers? (i) 9801 (ii) 99856 (iii) 998001 (iv) 657666025
Class 8 Squares and Square Roots Page 102"
Answers
if a number has 1 or 9 in the unit’s place, then it’s square ends in 1.
when a square number ends in 6, the number whose square it is, will have either 4 or 6 in unit’s place
when a square number ends in 9, the number whose square it is, will have either 3 or 7 in unit’s place
when a square number ends in5, the number whose square it is, will have 5 in unit’s place
when a square number ends in 4, the number whose square it is, will have either 2 or 8 in unit’s place
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Solution:
1) 1 and 9.
Since 1² and 9² give
1 at unit’s place, so these are the possible values of unit digit of the square
root.
2) 4 and 6
Since, 4²=16 and 6² =
36, hence, 4 and 6 are possible digits
3) 1 and 9
Since 1² and 9² give 1 at unit’s place, so these are the possible values of unit digit of the square root.
4) 5
Since, 5²= 25, hence 5 is
possible.
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Hope this will help you....