Things You'll Need
Instructions
Count the number of days in the month and divide that number by 7, which is the number of days in one week.
For example, if March has 31 days, there would be a total of 4.43 weeks in the month. (31 / 7 = 4.43).
Calculate the number of weeks in a month without a calculator by counting the number of full weeks by hand and dividing the remaining days by 7.
Take the number of full weeks and the answer for the remaining days and add them together.
For example, since there are 30 days in April, there are exactly four full weeks and two remaining days.
Divide the 2 by 7 to get 0.29.
Add the two numbers together and you can calculate the month of April has 4.29 weeks (4 + 0.29 = 4.29).