Question:
Find the average of even numbers from 12 to 588
Correct Answer
300
Solution And Explanation
Solution
Method (1) to find the average of the even numbers from 12 to 588
Shortcut Trick to find the average of the given continuous even numbers
The even numbers from 12 to 588 are
12, 14, 16, . . . . 588
After observing the above list of the even numbers from 12 to 588 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 12 to 588 form an Arithmetic Series.
In the Arithmetic Series of the even numbers from 12 to 588
The First Term (a) = 12
The Common Difference (d) = 2
And the last term (ℓ) = 588
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 588
= 12 + 588/2
= 600/2 = 300
Thus, the average of the even numbers from 12 to 588 = 300 Answer
Method (2) to find the average of the even numbers from 12 to 588
Finding the average of given continuous even numbers after finding their sum
The even numbers from 12 to 588 are
12, 14, 16, . . . . 588
The even numbers from 12 to 588 form an Arithmetic Series in which
The First Term (a) = 12
The Common Difference (d) = 2
And the last term (ℓ) = 588
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 588
588 = 12 + (n – 1) × 2
⇒ 588 = 12 + 2 n – 2
⇒ 588 = 12 – 2 + 2 n
⇒ 588 = 10 + 2 n
After transposing 10 to LHS
⇒ 588 – 10 = 2 n
⇒ 578 = 2 n
After rearranging the above expression
⇒ 2 n = 578
After transposing 2 to RHS
⇒ n = 578/2
⇒ n = 289
Thus, the number of terms of even numbers from 12 to 588 = 289
This means 588 is the 289th term.
Finding the sum of the given even numbers from 12 to 588
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 588
= 289/2 (12 + 588)
= 289/2 × 600
= 289 × 600/2
= 173400/2 = 86700
Thus, the sum of all terms of the given even numbers from 12 to 588 = 86700
And, the total number of terms = 289
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 588
= 86700/289 = 300
Thus, the average of the given even numbers from 12 to 588 = 300 Answer
Similar Questions
(1) Find the average of odd numbers from 9 to 1355
(2) Find the average of odd numbers from 7 to 433
(3) Find the average of odd numbers from 13 to 347
(4) What is the average of the first 1245 even numbers?
(5) Find the average of odd numbers from 13 to 1455
(6) What will be the average of the first 4186 odd numbers?
(7) What will be the average of the first 4370 odd numbers?
(8) Find the average of odd numbers from 9 to 541
(9) Find the average of the first 555 odd numbers.
(10) Find the average of even numbers from 10 to 768