Ferric Chloride solution weight

When I notice that ferric chloride is sold as $40\%$ solution w/v, does it mean weight / volume?

Is it a matter of for example adding $40$g of ferric chloride crystals to a water solution where the total volume will then be $100$ml?

Or do I have to workout via the molar mass of $\ce{FeCl3}$ to water? How do I calculate the weight of crystals necessary to create a $40\%$ solution of $\ce{FeCl3}$?

Thanks

EDIT:

The system seems to think this is a homework question (whatever that is). If I divide $100$ml of water (so $100$g) by $40\%$, I get $40$g of $\ce{FeCl3}$. If I dissolve $40$g of $\ce{FeCl3}$ in $100$ml of water, will I get a $40\%$ solution of $\ce{FeCl3}$? And a total volume of $114$ml? ($\ce{FeCl3}$ is $2.9\frac{\mathrm g}{\mathrm{cm^3}}$, so $40$g is approx $13.8$ml)?

• Welcome to Chemistry! This is a homework question. We have a policy which states that ‎you should show your thoughts and/or efforts into solving the problem. It'll make us certain that ‎we aren't doing your homework for you. Otherwise, this question may get closed.‎ Please edit in your full reasoning or thoughts on this. – M.A.R. Jul 7 '16 at 14:12
• What? That doesn't make any sense? – made2hack Jul 7 '16 at 14:59