Tactics 2 - How many armies to use?

In many situations, you may find yourself with a choice to place a number of armies before you start a blitz on an enemy. The question is, given the number of enemy armies and the number of countries you want to conquer, how many armies would you allocate for this purpose. Obviously, as a result of bad luck with the dice, some of your armies may get killed in the process. Of course no one can formulate this quantity accurately as it depends on chance, but a rough guide is always beneficial when confronted with such a choice.

Suppose E is the total number of enemy armies and T is the total number of enemy territories of which you would like to conquer.  The question is how many armies (F) would you place on your territory before the attack to make sure that you conquer the target enemy territories? A number of formulas were explored and some were found to be the most effective. The most common formulas are as follows:

• F = 2E. Use the ratio of 2:1 against the enemy which means that you need to place twice as much as the entire number of enemy armies you need to kill.  You will place this amount in the territory you want to start the attack from.
• F = 1.5E + T. For example, if enemy has 20 armies in 4 territories that you want to conquer in this turn, then place F = 1.5 * 20 + 4 = 34 armies and start to attack. Hopefully, you will have enough to cover your losses and be able to put at least one army in each conquered territory.
• F = 2E + T
• F = 2.5E + T
• F = 3E