Average
MCQs Math


Question:     Find the average of even numbers from 12 to 1862


Correct Answer  937

Solution And Explanation

Solution

Method (1) to find the average of the even numbers from 12 to 1862

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

The even numbers from 12 to 1862 are

12, 14, 16, . . . . 1862

After observing the above list of the even numbers from 12 to 1862 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 12 to 1862 form an Arithmetic Series.

In the Arithmetic Series of the even numbers from 12 to 1862

The First Term (a) = 12

The Common Difference (d) = 2

And the last term (ℓ) = 1862

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 12 to 1862

= 12 + 1862/2

= 1874/2 = 937

Thus, the average of the even numbers from 12 to 1862 = 937 Answer

Method (2) to find the average of the even numbers from 12 to 1862

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

The even numbers from 12 to 1862 are

12, 14, 16, . . . . 1862

The even numbers from 12 to 1862 form an Arithmetic Series in which

The First Term (a) = 12

The Common Difference (d) = 2

And the last term (ℓ) = 1862

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 12 to 1862

1862 = 12 + (n – 1) × 2

⇒ 1862 = 12 + 2 n – 2

⇒ 1862 = 12 – 2 + 2 n

⇒ 1862 = 10 + 2 n

After transposing 10 to LHS

⇒ 1862 – 10 = 2 n

⇒ 1852 = 2 n

After rearranging the above expression

⇒ 2 n = 1852

After transposing 2 to RHS

⇒ n = 1852/2

⇒ n = 926

Thus, the number of terms of even numbers from 12 to 1862 = 926

This means 1862 is the 926th term.

Finding the sum of the given even numbers from 12 to 1862

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 12 to 1862

= 926/2 (12 + 1862)

= 926/2 × 1874

= 926 × 1874/2

= 1735324/2 = 867662

Thus, the sum of all terms of the given even numbers from 12 to 1862 = 867662

And, the total number of terms = 926

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 12 to 1862

= 867662/926 = 937

Thus, the average of the given even numbers from 12 to 1862 = 937 Answer


Similar Questions

(1) What is the average of the first 1414 even numbers?

(2) Find the average of odd numbers from 15 to 1591

(3) Find the average of odd numbers from 3 to 267

(4) What is the average of the first 970 even numbers?

(5) Find the average of the first 2958 odd numbers.

(6) Find the average of odd numbers from 15 to 107

(7) Find the average of the first 582 odd numbers.

(8) Find the average of the first 1130 odd numbers.

(9) Find the average of odd numbers from 3 to 599

(10) Find the average of odd numbers from 7 to 281


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