Hello, I would like to know about the denominator and numerator and what part of the month or year they represents in the question below. For Ex: 1/3 is referring to what? And Why?

The Jason Corporation began 2021 with 12,000 shares of common stock, but it bought back 3,000 shares on September 1, 2021.the company's weighted average number of shares for purposes of its EPS calculations would be 11,000 shares:

12,000 shares outstanding for the year .......12,000 shares

3,000 shares reacquired X 1/3 year .............(1,000)shares

Weighted average shares outstanding ........11,000shares

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OR

12,000 shares outstanding X 2/3 year .........8,000 shares

9,000 shares outstanding X 1/3 year..........3,000shares

Weighted average shares outstanding .......11,000shares

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