Average
MCQs Math


Question:     Find the average of the first 4784 even numbers.


Correct Answer  4785

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 4784 even numbers are

2, 4, 6, 8, . . . . 4784 th terms

Calculation of the sum of the first 4784 even numbers

We can find the sum of the first 4784 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 4784 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 4784 even number,

n = 4784, a = 2, and d = 2

Thus, sum of the first 4784 even numbers

S4784 = 4784/2 [2 × 2 + (4784 – 1) 2]

= 4784/2 [4 + 4783 × 2]

= 4784/2 [4 + 9566]

= 4784/2 × 9570

= 4784/2 × 9570 4785

= 4784 × 4785 = 22891440

⇒ The sum of the first 4784 even numbers (S4784) = 22891440

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 4784 even numbers

= 47842 + 4784

= 22886656 + 4784 = 22891440

⇒ The sum of the first 4784 even numbers = 22891440

Calculation of the Average of the first 4784 even numbers

Formula to find the Average

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

Thus, The average of the first 4784 even numbers

= Sum of the first 4784 even numbers/4784

= 22891440/4784 = 4785

Thus, the average of the first 4784 even numbers = 4785 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 4784 even numbers = 4784 + 1 = 4785

Thus, the average of the first 4784 even numbers = 4785 Answer


Similar Questions

(1) Find the average of the first 2466 odd numbers.

(2) Find the average of odd numbers from 11 to 727

(3) What is the average of the first 1148 even numbers?

(4) Find the average of odd numbers from 11 to 439

(5) Find the average of even numbers from 10 to 2000

(6) Find the average of the first 4569 even numbers.

(7) Find the average of the first 2625 odd numbers.

(8) Find the average of the first 4095 even numbers.

(9) Find the average of the first 1021 odd numbers.

(10) Find the average of odd numbers from 5 to 1339


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