Chapter 6 . Squares and Square Roots

Exercise 6.1

1. What will be the unit digit of the squares of the following numbers?
(i) 81 (ii) 272 (iii) 799 (iv) 3853 (v) 1234 (vi) 26387 (vii) 52698 (viii) 99880  (ix) 12796 (x) 55555
Solution:  (i) The unit digit of the square of the number 81 is 1²=1 

(ii) The unit digit of the square of the number 272 is 2²=4 

(iii) The unit digit of the square of the number 799 is 9²=1  [9² = 81] 

(iv) The unit digit of the square of the number 3853 is 3²=9   

(v) The unit digit of the square of the number 1234 is 4²=6  [4²=16 ] 

(vi) The unit digit of the square of the number 26387 is 7²=9 [7²=49] 

(vii) The unit digit of the square of the number 52698 is 8²=4 [8²=64] 

(viii) The unit digit of the square of the number 99880 is 0²=0 

(ix) The unit digit of the square of the number 12796 is 6²=6  [6²=36] 

(x) The unit digit of the square of the number 55555 is 5²=5 [5²=25]