Average
MCQs Math


Question:     Find the average of the first 2795 even numbers.


Correct Answer  2796

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 the given numbers

The first 2795 even numbers are

2, 4, 6, 8, . . . . 2795 th terms

Calculation of the sum of the first 2795 even numbers

We can find the sum of the first 2795 even 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 2795 even 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 the first 2795 even number,

n = 2795, a = 2, and d = 2

Thus, sum of the first 2795 even numbers

S2795 = 2795/2 [2 × 2 + (2795 – 1) 2]

= 2795/2 [4 + 2794 × 2]

= 2795/2 [4 + 5588]

= 2795/2 × 5592

= 2795/2 × 5592 2796

= 2795 × 2796 = 7814820

⇒ The sum of the first 2795 even numbers (S2795) = 7814820

Shortcut Method to find the sum of the first n even numbers

Thus, the sum of the first n even numbers = n2 + n

Thus, the sum of the first 2795 even numbers

= 27952 + 2795

= 7812025 + 2795 = 7814820

⇒ The sum of the first 2795 even numbers = 7814820

Calculation of the Average of the first 2795 even numbers

Formula to find the Average

Average = Sum of the given numbers/Number of the numbers

Thus, The average of the first 2795 even numbers

= Sum of the first 2795 even numbers/2795

= 7814820/2795 = 2796

Thus, the average of the first 2795 even numbers = 2796 Answer

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

(1) The average of the first 2 even numbers

= 2 + 4/2

= 6/2 = 3

Thus, the average of the first 2 even numbers = 3

(2) The average of the first 3 even numbers

= 2 + 4 + 6/3

= 12/3 = 4

Thus, the average of the first 3 even numbers = 4

(3) The average of the first 4 even numbers

= 2 + 4 + 6 + 8/4

= 20/4 = 5

Thus, the average of the first 4 even numbers = 5

(4) The average of the first 5 even numbers

= 2 + 4 + 6 + 8 + 10/5

= 30/5 = 6

Thus, the average of the first 5 even numbers = 6

Thus, the Average of the First n even numbers = n + 1

Thus, the average of the first 2795 even numbers = 2795 + 1 = 2796

Thus, the average of the first 2795 even numbers = 2796 Answer


Similar Questions

(1) Find the average of the first 3496 odd numbers.

(2) What is the average of the first 206 even numbers?

(3) Find the average of odd numbers from 15 to 665

(4) Find the average of the first 585 odd numbers.

(5) Find the average of the first 4321 even numbers.

(6) Find the average of even numbers from 10 to 120

(7) Find the average of the first 1143 odd numbers.

(8) Find the average of even numbers from 4 to 860

(9) Find the average of the first 4519 even numbers.

(10) Find the average of the first 2766 even numbers.


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