Cost of a truffle

Question

A parent is buying two types of truffles for the children. The oldest likes white chocolate (w), the younger two like dark chocolate (d) and the spouse likes white chocolate (w). Four (w) cost the same as three (d). If the parent bought 3 (w) and 6 (d), and spent $49.50, how much was each dark chocolate truffle?

 

I'm having an issue with setting this up because I keep wanting to use that 4:3 ratio. Any help would be greatly appreciated!

Answer 1

4w=3d so w=¾d.

3w+6d=49.50=9d/4+6d=(9+24)d/4=49.50, 33d=198, d=$6.

So each dark chocolate truffle costs $6. (White costs $4.50)