Monthly Salary Calculation - Probation Period

Hi,
Wanted to know about the salary calculation on a monthly basis. We have a criteria of 6 months probation period for a new employee in which he/she is not liable for any leave except the weekly off i.e. sunday. So, if an employee is present for 20 days in a month of march, then what will be the ideal criteria or rule for his/her salary calculation for that month.
Is it like :- gross salary/31 * 20 days (no. of present days in a month)
or
Is it like :- gross salary/31 * 26 (including 4 sundays) - no. of not worked days
Should weekly offs be included in salary calculation or not?
I am very confused about this as I have gone through with lost of replies in Citehr.com, but still cant find the best answer as someone says that sundays should not be included in the calculation or others use to said that its compulsory to include that as it is compensatory offs.
Help me on that.
thanks

Hi Swati garu,
S the second 1 is right.
it is like :- gross salary/31 * 26 (including 4 sundays) - no. of not worked days
weekly offs be included in salary calculation or not?
Will clarify in a simple way.
U r working for a company. u attended the office the whole month (excluding Holidays & Sundays) even though u will b paid for the full month -31 days total.
Similary weekly offs SHOULD also b included.
Sincerely,
Sri
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