### Oh for the Mathematics of Yesteryear

A garrison of 600 men has just enough bread ... but, with the news that the enemy was planning an attack... How many ounces of bread a day must each man in the garrison be allowed, to hold out 45 days against the siege of the enemy?

### Tree Tops

A manager of a forestry company has to decide which trees to plant. What strategy for planting and felling would you recommend to the manager in order to maximise the profit?

### Thirty Nine, Seventy Five

We have exactly 100 coins. There are five different values of coins. We have decided to buy a piece of computer software for 39.75. We have the correct money, not a penny more, not a penny less! Can you discover what the five different types of coins are worth and how many of each we have saved?

# Debasing the Coinage

##### Stage: 3 Short Challenge Level:

240g.

There are 100 5p's in £5. The old coins weighed $100 \times 5.65 = 565$g, while the new coins weigh $100 \times 3.25 = 325$g. So your pocket weighs $565-325=240$g lighter.

This problem is taken from the UKMT Mathematical Challenges.