Average
MCQs Math


Question:     Find the average of even numbers from 6 to 32


Correct Answer  19

Solution And Explanation

Solution

Method (1) to find the average of the even numbers from 6 to 32

Shortcut Trick to find the average of the given continuous even numbers

The even numbers from 6 to 32 are

6, 8, 10, . . . . 32

After observing the above list of the even numbers from 6 to 32 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 6 to 32 form an Arithmetic Series.

In the Arithmetic Series of the even numbers from 6 to 32

The First Term (a) = 6

The Common Difference (d) = 2

And the last term (ℓ) = 32

The average of the numbers forming an Arithmetic Series

= The first term (a) + The last term (ℓ)/2

⇒ The average of numbers forming an Arithmetic Series = a + ℓ/2

Thus, the average of the even numbers from 6 to 32

= 6 + 32/2

= 38/2 = 19

Thus, the average of the even numbers from 6 to 32 = 19 Answer

Method (2) to find the average of the even numbers from 6 to 32

Finding the average of given continuous even numbers after finding their sum

The even numbers from 6 to 32 are

6, 8, 10, . . . . 32

The even numbers from 6 to 32 form an Arithmetic Series in which

The First Term (a) = 6

The Common Difference (d) = 2

And the last term (ℓ) = 32

The Average of the given numbers

= Sum of the given numbers/Total number of given numbers

Thus, to find the average of the given numbers, first, we need to find their sum and the total number of given numbers

Finding the number of terms

For an Arithmetic Series, the nth term

an = a + (n – 1) d

Where

a = First term

d = Common difference

n = number of terms

an = nth term

Thus, for the given series of the even numbers from 6 to 32

32 = 6 + (n – 1) × 2

⇒ 32 = 6 + 2 n – 2

⇒ 32 = 6 – 2 + 2 n

⇒ 32 = 4 + 2 n

After transposing 4 to LHS

⇒ 32 – 4 = 2 n

⇒ 28 = 2 n

After rearranging the above expression

⇒ 2 n = 28

After transposing 2 to RHS

⇒ n = 28/2

⇒ n = 14

Thus, the number of terms of even numbers from 6 to 32 = 14

This means 32 is the 14th term.

Finding the sum of the given even numbers from 6 to 32

The sum of all terms (S) in an Arithmetic Series

= n/2 (a + ℓ)

Where, n = number of terms

a = First term

And, ℓ = Last term

Thus, the sum of all terms (S) of the given even numbers from 6 to 32

= 14/2 (6 + 32)

= 14/2 × 38

= 14 × 38/2

= 532/2 = 266

Thus, the sum of all terms of the given even numbers from 6 to 32 = 266

And, the total number of terms = 14

Since, the average of the given numbers

= Sum of the given numbers/Total number of given numbers

Thus, the average of the given even numbers from 6 to 32

= 266/14 = 19

Thus, the average of the given even numbers from 6 to 32 = 19 Answer


Similar Questions

(1) Find the average of even numbers from 12 to 284

(2) Find the average of odd numbers from 15 to 1443

(3) What is the average of the first 481 even numbers?

(4) Find the average of the first 3816 even numbers.

(5) Find the average of even numbers from 8 to 1026

(6) Find the average of the first 2389 odd numbers.

(7) Find the average of the first 401 odd numbers.

(8) Find the average of the first 4273 even numbers.

(9) Find the average of even numbers from 12 to 722

(10) Find the average of even numbers from 10 to 1760


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