Question : Find the average of even numbers from 10 to 1116
Correct Answer 563
Solution & Explanation
Solution
Method (1) to find the average of the even numbers from 10 to 1116
Shortcut Trick to find the average of the given continuous even numbers
The even numbers from 10 to 1116 are
10, 12, 14, . . . . 1116
After observing the above list of the even numbers from 10 to 1116 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 10 to 1116 form an Arithmetic Series.
In the Arithmetic Series of the even numbers from 10 to 1116
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 1116
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 1116
= 10 + 1116/2
= 1126/2 = 563
Thus, the average of the even numbers from 10 to 1116 = 563 Answer
Method (2) to find the average of the even numbers from 10 to 1116
Finding the average of given continuous even numbers after finding their sum
The even numbers from 10 to 1116 are
10, 12, 14, . . . . 1116
The even numbers from 10 to 1116 form an Arithmetic Series in which
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 1116
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 1116
1116 = 10 + (n – 1) × 2
⇒ 1116 = 10 + 2 n – 2
⇒ 1116 = 10 – 2 + 2 n
⇒ 1116 = 8 + 2 n
After transposing 8 to LHS
⇒ 1116 – 8 = 2 n
⇒ 1108 = 2 n
After rearranging the above expression
⇒ 2 n = 1108
After transposing 2 to RHS
⇒ n = 1108/2
⇒ n = 554
Thus, the number of terms of even numbers from 10 to 1116 = 554
This means 1116 is the 554th term.
Finding the sum of the given even numbers from 10 to 1116
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 1116
= 554/2 (10 + 1116)
= 554/2 × 1126
= 554 × 1126/2
= 623804/2 = 311902
Thus, the sum of all terms of the given even numbers from 10 to 1116 = 311902
And, the total number of terms = 554
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 1116
= 311902/554 = 563
Thus, the average of the given even numbers from 10 to 1116 = 563 Answer
Similar Questions
(1) What will be the average of the first 4213 odd numbers?
(2) Find the average of odd numbers from 13 to 1025
(3) Find the average of the first 2667 odd numbers.
(4) Find the average of the first 315 odd numbers.
(5) Find the average of even numbers from 12 to 1090
(6) Find the average of even numbers from 4 to 626
(7) What is the average of the first 140 even numbers?
(8) Find the average of the first 2804 even numbers.
(9) What will be the average of the first 4428 odd numbers?
(10) What is the average of the first 591 even numbers?