How many odd numbers from 1 to 73?

There are 37 odd numbers from 1 to 73. Odd numbers are integers that are not divisible by 2, and they alternate with even numbers. In this case, the odd numbers from 1 to 73 are 1, 3, 5, ..., 71, 73. To count them, you can use the formula (last number - first number)/2 + 1 = (73-1)/2 + 1 = 36 + 1 = 37.