To calculate the number of odd numbers between two numbers, you could just make a list of all the odd numbers between the two numbers and then count them, but what fun would that be?
Instead, we have created a small formula to calculate exactly how many odd numbers there are between any two numbers.
To calculate the number of odd numbers between two numbers, you simply add 2 to the difference of the last odd number and the first odd number, and then divide the sum by 2. Here is the formula where N is the number of odd numbers.
N = (Last - First + 2) รท 2
Anyway, no need to get your calculator out. Instead, use the tool below to calculate the number of odd numbers between any two numbers.