How to take FVs
Step 1 - Check that you have enough built enough units to take the farming village.
If you click of the farming village you want to take, it will bring up a pop up box. There is a blue bar across the top saying how much you need and showing if you have enough.
For the third farm you will need units with their population totalling 10.
Note: This figure is not the number of units you have to send, it is the total units in your city. The population you have used building boats will be included in this figure. Although for your third farming village this isn't really important to know but the pop requirements are much higher on your 6th and 7th farming villages, so though I'd include it.
Step 2 - Figure out what units to send
On the pop up box, it shows what the farm is defended by. In this case three archers.
If you click on your barracks and press on the archers it will show you his attacking and defensive values. It doesn't matter if you haven't researched them yet, if you click on the + next to the pic of the divine envoys it will show all troops.
If you have a look at the right hand column of the conquest information on the right you will see the defensive values for archers are.
Blunt - 6
Sharp - 25
Ranged - 12
So as they are weakest against blunt attacks, you want to use units with blunt attacks. You can attack with other units if you wish but you will waste more units by doing so.
To figure out what type of attacks the different units have, click on the different units in your barracks and it says in the top left square of the conquest information box on the right, in the case of the archer posted above it has ranged attack of 8 (which is very low, so only defend with archers and not attack with them).
The ones with little daggers have blunt attacks and the number next to it gives the strength. There are a few different units which have daggers next to them.
Swordsmen with a value of 5. This is a very low figure so only use them to defend and not attack.
Horsmen with a value of 55. These are offensive units and are good ones to use to kill archers.
Divine envoys with a value of 35. These are generally rubbish units and I wouldn't advice building them but if you already have some, they would be good to send to attack archers.
You can also send your myth units if you have any when taking FV, so harpies could also be sent in this case as they're an offensive unit with a blunt attack.
Step 3 - Decide how many to send
If you go to your agora and use the simulator. Enter the number of units defending the farming village. In this case three archers and enter what blunt attacking units you have and press simulate, it will show you how many units you will lose and how many you will kill off.
In the case of your third farming village you only need to send 1 horsemen and will take no losses.