here in this question how we calculated the retained earnings

Pr. 15-163 -Treasury share transactions. The original sale of the $50 par value ordinary shares of Gray Company was recorded as follows: Cash Share Capital Ordinary 290,000 Share Premium-Ordinary 250,000 40,000 Instructions Record the treasury share transactions (given below) under the cost method: Transactions: (a) Bought 300 ordinary shares as treasury shares at \$62. (b) Sold 80 shares of treasury shares at $60. (c) Sold 40 treasury shares at $68. Solution 15-163 (a) Treasury Shares Cash 18,600 (b) Cash Retained Earnings Treasury Shares 4,800 18,600 (c) Cash. Share Premum-Treasury 2,720 Treasury Shares