Pardon my very ugly drawing. lol.

If 2/3 of Dan’s = 1/2 of Sam’s

then,
1/3 of Dan’s = 1/4 of Sam’s


[Refer to 1st Model]


Therefore, your working will be as such,

$56 / 7 = $8

$8 x 4 = $32


Here’s some things note:

As the fraction provided for both is not for the amount they have on their own, changing to the same denominator does not help. The fraction provided is for the amount of money they had individual. 1 unit for Dan will not be the same as 1 unit for Sam.

Looking at the model,
3 units for Dan = 1 WHOLE
4 units for Sam = 1 WHOLE

Dan has lesser than Sam. 1/2 of a smaller number can never be the same as 1/2 of a bigger number, even though the denominator is the same.

[Again, refer to model, this time observe the dotted lines in the 2nd model]

What we have done here is to identify what fraction each has of the TOTAL amount of money for both of them.

Hope this helps.