When you bought a pencil at the newsagent you tendered 1 and received 4 coins of different denominations as change how much was the pencil?

This depends on your currency, and what denomination coins are in use.

In the Eurozone there are 1c 2c 5c 10c 20c and 50c coins - as well a €1 and €2.

So in tendering €1.00 and getting four different denominations in change one could get any of the following

50c, 20c, 10c, 5c. - total 85c - pencil cost 15c

50c, 20c, 10c, 2c. - total 82c - pencil cost 18c

50c, 20c, 10c, 1c. - total 81c - pencil cost 19c

50c, 20c, 5c, 2c - total 77c - pencil cost 23c

50c, 20c, 5c, 1c - total 76c - pencil cost 24c

50c, 10c, 5c, 2c - total 67c - pencil cost 33c

50c, 10c, 5c, 1c - total 66c - pencil cost 34c

50c, 5c, 2c, 1c - total 58c - pencil cost 42c

20c, 10c, 5c, 2c - total 37c - pencil cost 63c

20c, 10c, 5c, 1c - total 36c - pencil cost 64c

10c, 5c, 2c, 1c - total 18c - pencil cost 82c

In US dollars there are 1c, 5c, 10c, 25c and 50c coins, as well as $1 coins

This gives a smaller range of possible values

50c, 25c, 10c, 5c - total 90c - pencil cost 10c

50c, 25c, 10c, 1c - total 86c - pencil cost 14c

25c, 10c, 5c, 1c - total 41c - pencil cost 59c