The total number of 3 digit even numbers is 450
Step-by-step explanation:
Step 1 :
We need to determine the number of 3 digit numbers which is even and the leftmost digit is not zero .
The 3 digits with left most digit not equal to zero starts from 100 and goes up to 998
If we consider only the even 3 digit numbers in this interval, this would form an arithmetic progression with the first number a = 100 and the common difference d = 2.
Step 2:
The last number l in this series is 998 .
So we have
a = 100
l = 998
d = 2
The nth term in the arithmetic progression is given by a + (n-1) d
so substituting the above values we get
100 + (n-1) 2 = 998
2n = 900 => n = 450
Step 3 :
Answer :
The total number of 3 digit even numbers is 450
