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.
February is also the only month of the calendar that once every six years and twice every 11 years consecutively, either back into the past or forward into the future, will have four full 7-day weeks.