Average
MCQs Math


Question:     Find the average of the first 2709 odd numbers.


Correct Answer  2709

Solution And Explanation

Explanation

Method to find the average

Step : (1) Find the sum of given numbers

Step: (2) Divide the sum of given number by the number of numbers. This will give the average of given numbers

The first 2709 odd numbers are

1, 3, 5, 7, 9, . . . . 2709 th terms

Calculation of the sum of the first 2709 odd numbers

We can find the sum of the first 2709 odd numbers by simply adding them, but this is a bit difficult. And if the list is long, it is very difficult to find their sum. So, in such a situation, we will use a formula to find the sum of given numbers that form a particular pattern.

Here, the list of the first 2709 odd numbers forms an Arithmetic series

In an Arithmetic Series, the common difference is the same. This means the difference between two consecutive terms are same in an Arithmetic Series.

The sum of n terms of an Arithmetic Series

Sn = n/2 [2a + (n – 1) d]

Where, n = number of terms, a = first term, and d = common difference

In the series of first 2709 odd number,

n = 2709, a = 1, and d = 2

Thus, sum of the first 2709 odd numbers

S2709 = 2709/2 [2 × 1 + (2709 – 1) 2]

= 2709/2 [2 + 2708 × 2]

= 2709/2 [2 + 5416]

= 2709/2 × 5418

= 2709/2 × 5418 2709

= 2709 × 2709 = 7338681

⇒ The sum of first 2709 odd numbers (Sn) = 7338681

Shortcut Method to find the sum of first n odd numbers

Thus, the sum of first n odd numbers = n2

Thus, the sum of first 2709 odd numbers

= 27092 = 7338681

⇒ The sum of first 2709 odd numbers = 7338681

Calculation of the Average of the first 2709 odd numbers

Formula to find the Average

Average = Sum of given numbers/Number of numbers

Thus, The average of the first 2709 odd numbers

= Sum of first 2709 odd numbers/2709

= 7338681/2709 = 2709

Thus, the average of the first 2709 odd numbers = 2709 Answer

Shortcut Trick to find the Average of the first n odd numbers

The average of the first 2 odd numbers

= 1 + 3/2

= 4/2 = 2

Thus, the average of the first 2 odd numbers = 2

The average of the first 3 odd numbers

= 1 + 3 + 5/3

= 9/3 = 3

Thus, the average of the first 3 odd numbers = 3

The average of the first 4 odd numbers

= 1 + 3 + 5 + 7/4

= 16/4 = 4

Thus, the average of the first 4 odd numbers = 4

The average of the first 5 odd numbers

= 1 + 3 + 5 + 7 + 9/5

= 25/5 = 5

Thus, the average of the first 5 odd numbers = 5

Thus, the Average of the the First n odd numbers = n

Thus, the average of the first 2709 odd numbers = 2709

Thus, the average of the first 2709 odd numbers = 2709 Answer


Similar Questions

(1) Find the average of the first 2540 odd numbers.

(2) Find the average of the first 2396 odd numbers.

(3) What is the average of the first 960 even numbers?

(4) What will be the average of the first 4541 odd numbers?

(5) Find the average of the first 1473 odd numbers.

(6) Find the average of odd numbers from 7 to 1429

(7) Find the average of the first 2521 odd numbers.

(8) Find the average of the first 2393 even numbers.

(9) Find the average of odd numbers from 3 to 465

(10) Find the average of the first 3265 odd numbers.


NCERT Solution and CBSE Notes for class twelve, eleventh, tenth, ninth, seventh, sixth, fifth, fourth and General Math for competitive Exams. ©