Question

sum of the first 'n' odd natural numbers in 961 . what is the value of 'n'

Answer 1

Hey ............... ✨✨✨✨

Here is your answer, ⬇⬇⬇⬇⬇

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The sequence consists of odd numbers : 1,3,5,7,9...

First term , a = 1

Common difference, d = 3-1 = 2

Sum of 'n' terms = 961

The formula is Sn = n/2 ( 2a + ( n-1 ) d )

961 = n/2 ( 2(1) + (n-1) 2)

961 = n ( 1 + n - 1 )

Both 1 and -1 will get cancel,

961 = n^2

n = √961

n = √ 31 x 31

n = 31

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Hope it helps you!✔✔✔✔

Answer 2

Sum of n numbers=(n/2)[2a+d(n-1)] is the formula

Now the odd numbers are 1,3, 5,7,11.......
Where

a = 1

d = 2
(why 2, d means the distance blw two numbers is 2)

n is that we should found in end.

961 = (n/2)[2(1) + 2(n-1)]

961 = (n/2)[2 + 2n - 2]

961 = (n/2)(2n)

961 = n^2

Here 961 can be written as 31 x 31

Then

31^2 = n^2

Applying sq root on bs gives

n = 31.


Thanks for questioning.

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