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Question:     Find the average of odd numbers from 5 to 1051


Correct Answer  528

Solution And Explanation

Solution

Method (1) to find the average of the odd numbers from 5 to 1051

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

The odd numbers from 5 to 1051 are

5, 7, 9, . . . . 1051

After observing the above list of the odd numbers from 5 to 1051 we find that the difference between two consecutive terms are equal. This means the list of the odd numbers from 5 to 1051 form an Arithmetic Series.

In the Arithmetic Series of the odd numbers from 5 to 1051

The First Term (a) = 5

The Common Difference (d) = 2

And the last term (ℓ) = 1051

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 odd numbers from 5 to 1051

= 5 + 1051/2

= 1056/2 = 528

Thus, the average of the odd numbers from 5 to 1051 = 528 Answer

Method (2) to find the average of the odd numbers from 5 to 1051

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

The odd numbers from 5 to 1051 are

5, 7, 9, . . . . 1051

The odd numbers from 5 to 1051 form an Arithmetic Series in which

The First Term (a) = 5

The Common Difference (d) = 2

And the last term (ℓ) = 1051

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 odd numbers from 5 to 1051

1051 = 5 + (n – 1) × 2

⇒ 1051 = 5 + 2 n – 2

⇒ 1051 = 5 – 2 + 2 n

⇒ 1051 = 3 + 2 n

After transposing 3 to LHS

⇒ 1051 – 3 = 2 n

⇒ 1048 = 2 n

After rearranging the above expression

⇒ 2 n = 1048

After transposing 2 to RHS

⇒ n = 1048/2

⇒ n = 524

Thus, the number of terms of odd numbers from 5 to 1051 = 524

This means 1051 is the 524th term.

Finding the sum of the given odd numbers from 5 to 1051

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 odd numbers from 5 to 1051

= 524/2 (5 + 1051)

= 524/2 × 1056

= 524 × 1056/2

= 553344/2 = 276672

Thus, the sum of all terms of the given odd numbers from 5 to 1051 = 276672

And, the total number of terms = 524

Since, the average of the given numbers

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

Thus, the average of the given odd numbers from 5 to 1051

= 276672/524 = 528

Thus, the average of the given odd numbers from 5 to 1051 = 528 Answer


Similar Questions

(1) Find the average of odd numbers from 3 to 515

(2) Find the average of even numbers from 10 to 126

(3) Find the average of the first 3228 even numbers.

(4) Find the average of the first 3239 even numbers.

(5) Find the average of odd numbers from 7 to 241

(6) Find the average of odd numbers from 15 to 1675

(7) Find the average of odd numbers from 7 to 961

(8) Find the average of odd numbers from 9 to 33

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