Question : Find the average of even numbers from 10 to 1626
Correct Answer 818
Solution & Explanation
Solution
Method (1) to find the average of the even numbers from 10 to 1626
Shortcut Trick to find the average of the given continuous even numbers
The even numbers from 10 to 1626 are
10, 12, 14, . . . . 1626
After observing the above list of the even numbers from 10 to 1626 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 10 to 1626 form an Arithmetic Series.
In the Arithmetic Series of the even numbers from 10 to 1626
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 1626
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 1626
= 10 + 1626/2
= 1636/2 = 818
Thus, the average of the even numbers from 10 to 1626 = 818 Answer
Method (2) to find the average of the even numbers from 10 to 1626
Finding the average of given continuous even numbers after finding their sum
The even numbers from 10 to 1626 are
10, 12, 14, . . . . 1626
The even numbers from 10 to 1626 form an Arithmetic Series in which
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 1626
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 1626
1626 = 10 + (n – 1) × 2
⇒ 1626 = 10 + 2 n – 2
⇒ 1626 = 10 – 2 + 2 n
⇒ 1626 = 8 + 2 n
After transposing 8 to LHS
⇒ 1626 – 8 = 2 n
⇒ 1618 = 2 n
After rearranging the above expression
⇒ 2 n = 1618
After transposing 2 to RHS
⇒ n = 1618/2
⇒ n = 809
Thus, the number of terms of even numbers from 10 to 1626 = 809
This means 1626 is the 809th term.
Finding the sum of the given even numbers from 10 to 1626
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 1626
= 809/2 (10 + 1626)
= 809/2 × 1636
= 809 × 1636/2
= 1323524/2 = 661762
Thus, the sum of all terms of the given even numbers from 10 to 1626 = 661762
And, the total number of terms = 809
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 1626
= 661762/809 = 818
Thus, the average of the given even numbers from 10 to 1626 = 818 Answer
Similar Questions
(1) Find the average of the first 4709 even numbers.
(2) Find the average of the first 4801 even numbers.
(3) Find the average of the first 4771 even numbers.
(4) Find the average of odd numbers from 13 to 1479
(5) Find the average of the first 2324 odd numbers.
(6) Find the average of the first 4354 even numbers.
(7) Find the average of the first 2356 odd numbers.
(8) Find the average of odd numbers from 13 to 957
(9) Find the average of even numbers from 12 to 1266
(10) Find the average of even numbers from 10 to 1406