Equity theory, most popularly known as equity theory of motivation, was first developed by John Stacey Adams, a workplace and behavioral psychologist, in 1963.
On average there are about 4.3 weeks in a month. Each week is 7 days, and there are normally either 30 or 31 days in a month, so there are usually between 4.2 and 4.4 weeks per month. The exception is February because it has fewer days, so there are about 4 weeks in that month. On average there are about 4.3 weeks in a month.
Every year has 7 months with 31 days. Each of these months have at least 3 weekdays that happen 5 times during the month. For example, August 2014 has 5 Fridays, 5 Saturdays and 5 Sundays. October 2014 has 5 Wednesdays, 5 Thursdays and 5 Fridays.