High School

Q10) What is the average of the first 126 odd natural numbers?

A) 126.5
B) 126
C) 125.5
D) 127

Answer :

To find the average of the first 126 odd natural numbers, we can use a formula for the average of a sequence of odd numbers.

The odd numbers sequence can be represented as:

1, 3, 5, 7, ...,

In general, the [tex]n[/tex]-th odd number is given by the formula:

[tex]a_n = 2n - 1[/tex]

So, the first 126 odd numbers are:

1, 3, 5, ...,

To find the sum of the first [tex]n[/tex] odd numbers, we use the formula:

[tex]\text{Sum} = n^2[/tex]

For [tex]n = 126[/tex], the sum of the first 126 odd numbers is:

[tex]126^2 = 15876[/tex]

Now, the average of these numbers is the sum divided by the number of terms, so:

[tex]\text{Average} = \frac{15876}{126}[/tex]

Calculating this gives:

[tex]\text{Average} = 126[/tex]

Therefore, the average of the first 126 odd natural numbers is 126.

The correct multiple-choice option is: B) 126.