The airmail rates to a country are shown.
Type | Mass | Cost |
Letters |
First 8 g | 24k¢ |
Every additional 4 g or less | 8k¢ | |
Postcards | Per piece | 70¢ |
Jack sent 2 postcards and a letter. The letter weighed 10 g. How much did Jack pay in total? Give your answer in terms of k in the simplest form.