The airmail rates to a country are shown.
Type | Mass | Cost |
Letters |
First 20 g | 23a¢ |
Every additional 10 g or less | 7a¢ | |
Postcards | Per piece | 60¢ |
Pierre sent 4 postcards and a letter. The letter weighed 24 g. How much did Pierre pay in total? Give your answer in terms of a in the simplest form.