# Working out ICopy from a current mirror [Mosfet]

I'm trying to solve for $I_{copy}$, but I've looked around on the internet and cannot find an explanation. However, I know the formula:

$I_{copy} =\frac{I_{REF} * W_1/L_1}{W_{REF}/L_{REF}}$

but don't understand how to work this out from the circuit diagram.

Attached is an image explanation my problem. Answer for:

• The circuit on the left: $I_{copy}=\frac{2}{8I_{REF}}$

• The circuit on the right: $I_{copy}= 7I_{REF}$