The airmail rates to a country are shown.
Type | Mass | Cost |
Letters |
First 12 g | 23s¢ |
Every additional 6 g or less | 12s¢ | |
Postcards | Per piece | 90¢ |
Ahmad sent 3 postcards and a letter. The letter weighed 28 g. How much did Ahmad pay in total? Give your answer in terms of s in the simplest form.