Question

How many even numbers are there between 21 and 41

Answer 1

Answer:

There are 10 even no. in between 21 and 41

Step-by-step explanation:

The even numbers are -  22, 24, 26 ,28, 30, 32, 34, 36, 38, 40

Answer 2

The total number of even numbers between 21 and 41 = 10

Step-by-step explanation:

The all even numbers between 21 and 41 are:

22, 24, 26 ,28, 30, 32, 34, 36, 38 and  40

To find, the total number of even numbers between 21 and 41 = ?

The all even numbers between 21 and 41 are:

22,24, 26,28, 30, 32,34, 36,38 and  40

The given numbers are in AP.

Here, first term(a) = 22, common difference(d) = 24 - 22 = 2 and

$a_{n} =40$

Let the total number of even numbers between 21 and 41 = n

∴ $a_{n} =a+(n-1)d$

⇒ 22 + (n - 1)2 = 40

⇒ (n - 1)2 = 40 - 22 = 18

⇒ n - 1 = $\dfrac{18}{2} =9$

⇒ n = 9 + 1 = 10

∴ The total number of even numbers between 21 and 41 = 10