Question

without adding find the sum of first 11odd number ​

Answer 1

Answer:

The number series 1, 3, 5, 7, 9, . . . . , 21. Therefore, 121 is the sum of first 11 odd numbers.

Hope it will help you.

Answer 2

Answer:

11×11

=121

Because the first 11 odd numbers witll add up to 121 and adding the first 11 odd numbers is similar to squaring 11. This a shortcut trick of adding and also a quick method of solving for competitive exams, which I learnt in school.