Question : What is the average of the first 1314 even numbers?
Correct Answer 1315
Solution & Explanation
Explanation
Method to find the average
Step : (1) Find the sum of given numbers
Step: (2) Divide the sum of given number by the number of numbers. This will give the average of the given numbers
The first 1314 even numbers are
2, 4, 6, 8, . . . . 1314 th terms
Calculation of the sum of the first 1314 even numbers
We can find the sum of the first 1314 even numbers by simply adding them, but this is a bit difficult. And if the list is long, it is very difficult to find their sum. So, in such a situation, we will use a formula to find the sum of given numbers that form a particular pattern.
Here, the list of the first 1314 even numbers forms an Arithmetic series
In an Arithmetic Series, the common difference is the same. This means the difference between two consecutive terms are same in an Arithmetic Series.
The sum of n terms of an Arithmetic Series
Sn = n/2 [2a + (n – 1) d]
Where, n = number of terms, a = first term, and d = common difference
In the series of the first 1314 even number,
n = 1314, a = 2, and d = 2
Thus, sum of the first 1314 even numbers
S1314 = 1314/2 [2 × 2 + (1314 – 1) 2]
= 1314/2 [4 + 1313 × 2]
= 1314/2 [4 + 2626]
= 1314/2 × 2630
= 1314/2 × 2630 1315
= 1314 × 1315 = 1727910
⇒ The sum of the first 1314 even numbers (S1314) = 1727910
Shortcut Method to find the sum of the first n even numbers
Thus, the sum of the first n even numbers = n2 + n
Thus, the sum of the first 1314 even numbers
= 13142 + 1314
= 1726596 + 1314 = 1727910
⇒ The sum of the first 1314 even numbers = 1727910
Calculation of the Average of the first 1314 even numbers
Formula to find the Average
Average = Sum of the given numbers/Number of the numbers
Thus, The average of the first 1314 even numbers
= Sum of the first 1314 even numbers/1314
= 1727910/1314 = 1315
Thus, the average of the first 1314 even numbers = 1315 Answer
Shortcut Trick to find the Average of the first n even numbers
(1) The average of the first 2 even numbers
= 2 + 4/2
= 6/2 = 3
Thus, the average of the first 2 even numbers = 3
(2) The average of the first 3 even numbers
= 2 + 4 + 6/3
= 12/3 = 4
Thus, the average of the first 3 even numbers = 4
(3) The average of the first 4 even numbers
= 2 + 4 + 6 + 8/4
= 20/4 = 5
Thus, the average of the first 4 even numbers = 5
(4) The average of the first 5 even numbers
= 2 + 4 + 6 + 8 + 10/5
= 30/5 = 6
Thus, the average of the first 5 even numbers = 6
Thus, the Average of the First n even numbers = n + 1
Thus, the average of the first 1314 even numbers = 1314 + 1 = 1315
Thus, the average of the first 1314 even numbers = 1315 Answer
Similar Questions
(1) Find the average of the first 540 odd numbers.
(2) Find the average of odd numbers from 9 to 1261
(3) Find the average of odd numbers from 7 to 1439
(4) What is the average of the first 895 even numbers?
(5) What is the average of the first 1340 even numbers?
(6) Find the average of the first 2618 odd numbers.
(7) What is the average of the first 596 even numbers?
(8) Find the average of the first 792 odd numbers.
(9) Find the average of the first 4000 even numbers.
(10) Find the average of odd numbers from 15 to 1307