Question:
Find the average of even numbers from 4 to 1586
Correct Answer
795
Solution And Explanation
Solution
Method (1) to find the average of the even numbers from 4 to 1586
Shortcut Trick to find the average of the given continuous even numbers
The even numbers from 4 to 1586 are
4, 6, 8, . . . . 1586
After observing the above list of the even numbers from 4 to 1586 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 4 to 1586 form an Arithmetic Series.
In the Arithmetic Series of the even numbers from 4 to 1586
The First Term (a) = 4
The Common Difference (d) = 2
And the last term (ℓ) = 1586
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 4 to 1586
= 4 + 1586/2
= 1590/2 = 795
Thus, the average of the even numbers from 4 to 1586 = 795 Answer
Method (2) to find the average of the even numbers from 4 to 1586
Finding the average of given continuous even numbers after finding their sum
The even numbers from 4 to 1586 are
4, 6, 8, . . . . 1586
The even numbers from 4 to 1586 form an Arithmetic Series in which
The First Term (a) = 4
The Common Difference (d) = 2
And the last term (ℓ) = 1586
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 4 to 1586
1586 = 4 + (n – 1) × 2
⇒ 1586 = 4 + 2 n – 2
⇒ 1586 = 4 – 2 + 2 n
⇒ 1586 = 2 + 2 n
After transposing 2 to LHS
⇒ 1586 – 2 = 2 n
⇒ 1584 = 2 n
After rearranging the above expression
⇒ 2 n = 1584
After transposing 2 to RHS
⇒ n = 1584/2
⇒ n = 792
Thus, the number of terms of even numbers from 4 to 1586 = 792
This means 1586 is the 792th term.
Finding the sum of the given even numbers from 4 to 1586
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 4 to 1586
= 792/2 (4 + 1586)
= 792/2 × 1590
= 792 × 1590/2
= 1259280/2 = 629640
Thus, the sum of all terms of the given even numbers from 4 to 1586 = 629640
And, the total number of terms = 792
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 4 to 1586
= 629640/792 = 795
Thus, the average of the given even numbers from 4 to 1586 = 795 Answer
Similar Questions
(1) What will be the average of the first 4772 odd numbers?
(2) Find the average of the first 3407 odd numbers.
(3) What will be the average of the first 4724 odd numbers?
(4) Find the average of even numbers from 4 to 828
(5) What is the average of the first 869 even numbers?
(6) Find the average of odd numbers from 15 to 1495
(7) Find the average of odd numbers from 3 to 1039
(8) What is the average of the first 533 even numbers?
(9) Find the average of odd numbers from 7 to 1399
(10) Find the average of odd numbers from 11 to 391