Question:
Find the average of even numbers from 10 to 562
Correct Answer
286
Solution And Explanation
Solution
Method (1) to find the average of the even numbers from 10 to 562
Shortcut Trick to find the average of the given continuous even numbers
The even numbers from 10 to 562 are
10, 12, 14, . . . . 562
After observing the above list of the even numbers from 10 to 562 we find that the difference between two consecutive terms are equal. This means the list of the even numbers from 10 to 562 form an Arithmetic Series.
In the Arithmetic Series of the even numbers from 10 to 562
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 562
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 562
= 10 + 562/2
= 572/2 = 286
Thus, the average of the even numbers from 10 to 562 = 286 Answer
Method (2) to find the average of the even numbers from 10 to 562
Finding the average of given continuous even numbers after finding their sum
The even numbers from 10 to 562 are
10, 12, 14, . . . . 562
The even numbers from 10 to 562 form an Arithmetic Series in which
The First Term (a) = 10
The Common Difference (d) = 2
And the last term (ℓ) = 562
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 562
562 = 10 + (n – 1) × 2
⇒ 562 = 10 + 2 n – 2
⇒ 562 = 10 – 2 + 2 n
⇒ 562 = 8 + 2 n
After transposing 8 to LHS
⇒ 562 – 8 = 2 n
⇒ 554 = 2 n
After rearranging the above expression
⇒ 2 n = 554
After transposing 2 to RHS
⇒ n = 554/2
⇒ n = 277
Thus, the number of terms of even numbers from 10 to 562 = 277
This means 562 is the 277th term.
Finding the sum of the given even numbers from 10 to 562
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 562
= 277/2 (10 + 562)
= 277/2 × 572
= 277 × 572/2
= 158444/2 = 79222
Thus, the sum of all terms of the given even numbers from 10 to 562 = 79222
And, the total number of terms = 277
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 562
= 79222/277 = 286
Thus, the average of the given even numbers from 10 to 562 = 286 Answer
Similar Questions
(1) Find the average of even numbers from 8 to 766
(2) Find the average of odd numbers from 7 to 521
(3) Find the average of the first 3230 odd numbers.
(4) Find the average of the first 1817 odd numbers.
(5) Find the average of even numbers from 4 to 222
(6) Find the average of odd numbers from 5 to 1265
(7) Find the average of the first 3488 odd numbers.
(8) Find the average of even numbers from 12 to 1442
(9) Find the average of odd numbers from 3 to 477
(10) Find the average of even numbers from 6 to 712