Question : Find the average of even numbers from 12 to 1164
Correct Answer 588
Solution & Explanation
Solution
Method (1) to find the average of the even numbers from 12 to 1164
Shortcut Trick to find the average of the given continuous even numbers
The even numbers from 12 to 1164 are
12, 14, 16, . . . . 1164
After observing the above list of the even numbers from 12 to 1164 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 12 to 1164 form an Arithmetic Series.
In the Arithmetic Series of the even numbers from 12 to 1164
The First Term (a) = 12
The Common Difference (d) = 2
And the last term (ℓ) = 1164
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 12 to 1164
= 12 + 1164/2
= 1176/2 = 588
Thus, the average of the even numbers from 12 to 1164 = 588 Answer
Method (2) to find the average of the even numbers from 12 to 1164
Finding the average of given continuous even numbers after finding their sum
The even numbers from 12 to 1164 are
12, 14, 16, . . . . 1164
The even numbers from 12 to 1164 form an Arithmetic Series in which
The First Term (a) = 12
The Common Difference (d) = 2
And the last term (ℓ) = 1164
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 12 to 1164
1164 = 12 + (n – 1) × 2
⇒ 1164 = 12 + 2 n – 2
⇒ 1164 = 12 – 2 + 2 n
⇒ 1164 = 10 + 2 n
After transposing 10 to LHS
⇒ 1164 – 10 = 2 n
⇒ 1154 = 2 n
After rearranging the above expression
⇒ 2 n = 1154
After transposing 2 to RHS
⇒ n = 1154/2
⇒ n = 577
Thus, the number of terms of even numbers from 12 to 1164 = 577
This means 1164 is the 577th term.
Finding the sum of the given even numbers from 12 to 1164
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 12 to 1164
= 577/2 (12 + 1164)
= 577/2 × 1176
= 577 × 1176/2
= 678552/2 = 339276
Thus, the sum of all terms of the given even numbers from 12 to 1164 = 339276
And, the total number of terms = 577
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 12 to 1164
= 339276/577 = 588
Thus, the average of the given even numbers from 12 to 1164 = 588 Answer
Similar Questions
(1) Find the average of even numbers from 8 to 814
(2) Find the average of the first 1108 odd numbers.
(3) Find the average of odd numbers from 15 to 21
(4) Find the average of the first 2944 even numbers.
(5) Find the average of odd numbers from 11 to 1393
(6) Find the average of odd numbers from 11 to 1353
(7) Find the average of the first 3981 odd numbers.
(8) Find the average of the first 3081 even numbers.
(9) Find the average of the first 207 odd numbers.
(10) Find the average of the first 3430 even numbers.