Question : Find the average of even numbers from 10 to 1316
Correct Answer 663
Solution & Explanation
Solution
Method (1) to find the average of the even numbers from 10 to 1316
Shortcut Trick to find the average of the given continuous even numbers
The even numbers from 10 to 1316 are
10, 12, 14, . . . . 1316
After observing the above list of the even numbers from 10 to 1316 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 10 to 1316 form an Arithmetic Series.
In the Arithmetic Series of the even numbers from 10 to 1316
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 1316
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 1316
= 10 + 1316/2
= 1326/2 = 663
Thus, the average of the even numbers from 10 to 1316 = 663 Answer
Method (2) to find the average of the even numbers from 10 to 1316
Finding the average of given continuous even numbers after finding their sum
The even numbers from 10 to 1316 are
10, 12, 14, . . . . 1316
The even numbers from 10 to 1316 form an Arithmetic Series in which
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 1316
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 1316
1316 = 10 + (n – 1) × 2
⇒ 1316 = 10 + 2 n – 2
⇒ 1316 = 10 – 2 + 2 n
⇒ 1316 = 8 + 2 n
After transposing 8 to LHS
⇒ 1316 – 8 = 2 n
⇒ 1308 = 2 n
After rearranging the above expression
⇒ 2 n = 1308
After transposing 2 to RHS
⇒ n = 1308/2
⇒ n = 654
Thus, the number of terms of even numbers from 10 to 1316 = 654
This means 1316 is the 654th term.
Finding the sum of the given even numbers from 10 to 1316
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 1316
= 654/2 (10 + 1316)
= 654/2 × 1326
= 654 × 1326/2
= 867204/2 = 433602
Thus, the sum of all terms of the given even numbers from 10 to 1316 = 433602
And, the total number of terms = 654
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 1316
= 433602/654 = 663
Thus, the average of the given even numbers from 10 to 1316 = 663 Answer
Similar Questions
(1) Find the average of the first 2245 even numbers.
(2) Find the average of the first 3638 odd numbers.
(3) Find the average of even numbers from 6 to 1948
(4) Find the average of the first 1337 odd numbers.
(5) Find the average of the first 3299 odd numbers.
(6) Find the average of odd numbers from 15 to 987
(7) Find the average of the first 4732 even numbers.
(8) What is the average of the first 818 even numbers?
(9) Find the average of the first 2790 odd numbers.
(10) What is the average of the first 419 even numbers?