Square of a Number

Square of a number having 5 at its one’s place and 2 or more digits at its ten's, hundred's,......etc. place is equal to 25 followed by the product of the number of the remaining digits and the number exceeded by 1.

$Square of a Number$

You may write the products in one line.

a) 5 5 (b) 6 5 (c) 7 5 (d) 1 0 5

       x 5 5                    x 6 5                x 7 5                   x 1 0 5

      ______                 ______                 ______                 _______

(e) 2 0 5 (f) 3 4 5 (g) 9 9 5

   x 2 0 5                    x 3 4 5                   x 9 9 5

________                  ________               ________

Check answers:

(a) 3025

5 x 6 = 30

(b) 4225

6 x 7 = 42

(c) 5625

7 x 8 = 56

(d) 11025

10 x 11 = 110

(e) 42025

20 x 21 = 420

(f) 119025

34 x 35 = 1190

(g) 990025

99 x 100 = 9900