Average
MCQs Math


Question:     Find the average of even numbers from 10 to 1366


Correct Answer  688

Solution And Explanation

Solution

Method (1) to find the average of the even numbers from 10 to 1366

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

The even numbers from 10 to 1366 are

10, 12, 14, . . . . 1366

After observing the above list of the even numbers from 10 to 1366 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 10 to 1366 form an Arithmetic Series.

In the Arithmetic Series of the even numbers from 10 to 1366

The First Term (a) = 10

The Common Difference (d) = 2

And the last term (ℓ) = 1366

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 1366

= 10 + 1366/2

= 1376/2 = 688

Thus, the average of the even numbers from 10 to 1366 = 688 Answer

Method (2) to find the average of the even numbers from 10 to 1366

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

The even numbers from 10 to 1366 are

10, 12, 14, . . . . 1366

The even numbers from 10 to 1366 form an Arithmetic Series in which

The First Term (a) = 10

The Common Difference (d) = 2

And the last term (ℓ) = 1366

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 1366

1366 = 10 + (n – 1) × 2

⇒ 1366 = 10 + 2 n – 2

⇒ 1366 = 10 – 2 + 2 n

⇒ 1366 = 8 + 2 n

After transposing 8 to LHS

⇒ 1366 – 8 = 2 n

⇒ 1358 = 2 n

After rearranging the above expression

⇒ 2 n = 1358

After transposing 2 to RHS

⇒ n = 1358/2

⇒ n = 679

Thus, the number of terms of even numbers from 10 to 1366 = 679

This means 1366 is the 679th term.

Finding the sum of the given even numbers from 10 to 1366

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 1366

= 679/2 (10 + 1366)

= 679/2 × 1376

= 679 × 1376/2

= 934304/2 = 467152

Thus, the sum of all terms of the given even numbers from 10 to 1366 = 467152

And, the total number of terms = 679

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 1366

= 467152/679 = 688

Thus, the average of the given even numbers from 10 to 1366 = 688 Answer


Similar Questions

(1) Find the average of the first 4372 even numbers.

(2) Find the average of odd numbers from 9 to 299

(3) Find the average of even numbers from 12 to 1238

(4) Find the average of odd numbers from 11 to 587

(5) Find the average of odd numbers from 13 to 201

(6) What is the average of the first 406 even numbers?

(7) Find the average of even numbers from 12 to 486

(8) Find the average of the first 3618 odd numbers.

(9) Find the average of the first 3176 even numbers.

(10) Find the average of the first 4773 even numbers.


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