Question:
Find the average of even numbers from 12 to 1610
Correct Answer
811
Solution And Explanation
Solution
Method (1) to find the average of the even numbers from 12 to 1610
Shortcut Trick to find the average of the given continuous even numbers
The even numbers from 12 to 1610 are
12, 14, 16, . . . . 1610
After observing the above list of the even numbers from 12 to 1610 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 12 to 1610 form an Arithmetic Series.
In the Arithmetic Series of the even numbers from 12 to 1610
The First Term (a) = 12
The Common Difference (d) = 2
And the last term (ℓ) = 1610
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 1610
= 12 + 1610/2
= 1622/2 = 811
Thus, the average of the even numbers from 12 to 1610 = 811 Answer
Method (2) to find the average of the even numbers from 12 to 1610
Finding the average of given continuous even numbers after finding their sum
The even numbers from 12 to 1610 are
12, 14, 16, . . . . 1610
The even numbers from 12 to 1610 form an Arithmetic Series in which
The First Term (a) = 12
The Common Difference (d) = 2
And the last term (ℓ) = 1610
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 1610
1610 = 12 + (n – 1) × 2
⇒ 1610 = 12 + 2 n – 2
⇒ 1610 = 12 – 2 + 2 n
⇒ 1610 = 10 + 2 n
After transposing 10 to LHS
⇒ 1610 – 10 = 2 n
⇒ 1600 = 2 n
After rearranging the above expression
⇒ 2 n = 1600
After transposing 2 to RHS
⇒ n = 1600/2
⇒ n = 800
Thus, the number of terms of even numbers from 12 to 1610 = 800
This means 1610 is the 800th term.
Finding the sum of the given even numbers from 12 to 1610
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 1610
= 800/2 (12 + 1610)
= 800/2 × 1622
= 800 × 1622/2
= 1297600/2 = 648800
Thus, the sum of all terms of the given even numbers from 12 to 1610 = 648800
And, the total number of terms = 800
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 1610
= 648800/800 = 811
Thus, the average of the given even numbers from 12 to 1610 = 811 Answer
Similar Questions
(1) Find the average of even numbers from 4 to 1320
(2) What is the average of the first 1330 even numbers?
(3) Find the average of the first 1867 odd numbers.
(4) Find the average of odd numbers from 5 to 19
(5) Find the average of odd numbers from 9 to 561
(6) Find the average of even numbers from 12 to 1050
(7) Find the average of the first 3325 even numbers.
(8) Find the average of odd numbers from 11 to 109
(9) Find the average of the first 2612 odd numbers.
(10) Find the average of the first 2520 even numbers.