Average
MCQs Math


Question:     Find the average of the first 1695 odd numbers.


Correct Answer  1695

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 1695 odd numbers are

1, 3, 5, 7, 9, . . . . 1695 th terms

Calculation of the sum of the first 1695 odd numbers

We can find the sum of the first 1695 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 1695 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 1695 odd number,

n = 1695, a = 1, and d = 2

Thus, sum of the first 1695 odd numbers

S1695 = 1695/2 [2 × 1 + (1695 – 1) 2]

= 1695/2 [2 + 1694 × 2]

= 1695/2 [2 + 3388]

= 1695/2 × 3390

= 1695/2 × 3390 1695

= 1695 × 1695 = 2873025

⇒ The sum of first 1695 odd numbers (Sn) = 2873025

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 1695 odd numbers

= 16952 = 2873025

⇒ The sum of first 1695 odd numbers = 2873025

Calculation of the Average of the first 1695 odd numbers

Formula to find the Average

Average = Sum of given numbers/Number of numbers

Thus, The average of the first 1695 odd numbers

= Sum of first 1695 odd numbers/1695

= 2873025/1695 = 1695

Thus, the average of the first 1695 odd numbers = 1695 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 1695 odd numbers = 1695

Thus, the average of the first 1695 odd numbers = 1695 Answer


Similar Questions

(1) Find the average of the first 2696 odd numbers.

(2) Find the average of even numbers from 8 to 986

(3) What will be the average of the first 4156 odd numbers?

(4) What is the average of the first 1986 even numbers?

(5) Find the average of even numbers from 6 to 1026

(6) Find the average of odd numbers from 15 to 781

(7) Find the average of even numbers from 8 to 1380

(8) Find the average of odd numbers from 11 to 1495

(9) Find the average of the first 4760 even numbers.

(10) Find the average of the first 741 odd numbers.


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