Chemistry Moles question?

Question

A method needs 2.5% (w/v) sodium acetate. You need to make up 200ml but you only have the hydrated form (CH3COONa3H2O mol. Weight 136). How much would you weigh out?

If you can show me the working I would be greatly appreciated! Or even just a hint

Answer 1

wt of CH3COONa needed to produce 200 ml soln

= (2.5 g/ 100 ml ) ( 200 ml ) = 5 g of CH3COONa

wt. of CH3COONa.3H2O = 5 X 136 / 82 = 8.29 g

therefore you need to weigh 8.29 g CH3COONa.3H2O

Answer 2

136 g of the hydrated form has 54 g ( / ml) of water

Now assume a 1 l soln and calculate.