Average
MCQs Math


Question:     Find the average of even numbers from 10 to 1650


Correct Answer  830

Solution And Explanation

Solution

Method (1) to find the average of the even numbers from 10 to 1650

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

The even numbers from 10 to 1650 are

10, 12, 14, . . . . 1650

After observing the above list of the even numbers from 10 to 1650 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 10 to 1650 form an Arithmetic Series.

In the Arithmetic Series of the even numbers from 10 to 1650

The First Term (a) = 10

The Common Difference (d) = 2

And the last term (ℓ) = 1650

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 10 to 1650

= 10 + 1650/2

= 1660/2 = 830

Thus, the average of the even numbers from 10 to 1650 = 830 Answer

Method (2) to find the average of the even numbers from 10 to 1650

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

The even numbers from 10 to 1650 are

10, 12, 14, . . . . 1650

The even numbers from 10 to 1650 form an Arithmetic Series in which

The First Term (a) = 10

The Common Difference (d) = 2

And the last term (ℓ) = 1650

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 10 to 1650

1650 = 10 + (n – 1) × 2

⇒ 1650 = 10 + 2 n – 2

⇒ 1650 = 10 – 2 + 2 n

⇒ 1650 = 8 + 2 n

After transposing 8 to LHS

⇒ 1650 – 8 = 2 n

⇒ 1642 = 2 n

After rearranging the above expression

⇒ 2 n = 1642

After transposing 2 to RHS

⇒ n = 1642/2

⇒ n = 821

Thus, the number of terms of even numbers from 10 to 1650 = 821

This means 1650 is the 821th term.

Finding the sum of the given even numbers from 10 to 1650

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 10 to 1650

= 821/2 (10 + 1650)

= 821/2 × 1660

= 821 × 1660/2

= 1362860/2 = 681430

Thus, the sum of all terms of the given even numbers from 10 to 1650 = 681430

And, the total number of terms = 821

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 10 to 1650

= 681430/821 = 830

Thus, the average of the given even numbers from 10 to 1650 = 830 Answer


Similar Questions

(1) Find the average of even numbers from 10 to 1898

(2) Find the average of the first 3368 even numbers.

(3) Find the average of even numbers from 10 to 376

(4) What is the average of the first 805 even numbers?

(5) Find the average of odd numbers from 11 to 1035

(6) What will be the average of the first 4599 odd numbers?

(7) Find the average of the first 2340 even numbers.

(8) Find the average of the first 2954 odd numbers.

(9) Find the average of even numbers from 10 to 214

(10) Find the average of even numbers from 12 to 430


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