Question : Find the average of even numbers from 10 to 1470
Correct Answer 740
Solution & Explanation
Solution
Method (1) to find the average of the even numbers from 10 to 1470
Shortcut Trick to find the average of the given continuous even numbers
The even numbers from 10 to 1470 are
10, 12, 14, . . . . 1470
After observing the above list of the even numbers from 10 to 1470 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 10 to 1470 form an Arithmetic Series.
In the Arithmetic Series of the even numbers from 10 to 1470
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 1470
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 1470
= 10 + 1470/2
= 1480/2 = 740
Thus, the average of the even numbers from 10 to 1470 = 740 Answer
Method (2) to find the average of the even numbers from 10 to 1470
Finding the average of given continuous even numbers after finding their sum
The even numbers from 10 to 1470 are
10, 12, 14, . . . . 1470
The even numbers from 10 to 1470 form an Arithmetic Series in which
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 1470
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 1470
1470 = 10 + (n – 1) × 2
⇒ 1470 = 10 + 2 n – 2
⇒ 1470 = 10 – 2 + 2 n
⇒ 1470 = 8 + 2 n
After transposing 8 to LHS
⇒ 1470 – 8 = 2 n
⇒ 1462 = 2 n
After rearranging the above expression
⇒ 2 n = 1462
After transposing 2 to RHS
⇒ n = 1462/2
⇒ n = 731
Thus, the number of terms of even numbers from 10 to 1470 = 731
This means 1470 is the 731th term.
Finding the sum of the given even numbers from 10 to 1470
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 1470
= 731/2 (10 + 1470)
= 731/2 × 1480
= 731 × 1480/2
= 1081880/2 = 540940
Thus, the sum of all terms of the given even numbers from 10 to 1470 = 540940
And, the total number of terms = 731
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 1470
= 540940/731 = 740
Thus, the average of the given even numbers from 10 to 1470 = 740 Answer
Similar Questions
(1) Find the average of odd numbers from 11 to 929
(2) Find the average of even numbers from 6 to 790
(3) Find the average of odd numbers from 15 to 235
(4) Find the average of odd numbers from 9 to 733
(5) Find the average of even numbers from 10 to 1416
(6) Find the average of the first 3785 odd numbers.
(7) Find the average of odd numbers from 7 to 1079
(8) What is the average of the first 1091 even numbers?
(9) What will be the average of the first 4060 odd numbers?
(10) What is the average of the first 1278 even numbers?