how to find share premium ?

EQUITY BE15-4: Ravonette Corporation issued 300 shares of $10 par value ordinary shares and 100 shares of $50 par value preference shares for a lump sum of $13,500. The ordinary shares have a market value of $20 per share, and the preference shares have a market value of $90 per share. Journal entry (Proportional): 13,500 Cash Share Capital-Preference (100 X $50) Share Premium-Preference Share Capital-Ordinary (300 X $10) Share Premium-Ordinary 5,000 3,100 3,000 2,400