One way we can solve this is to start at x and to work from there.
Since x represents the number of baseball cards that Barry's brother has, and the closest phrase to it is "two-thirds of the number of cards", we can start by writing that as "2/3 of x", or (2/3) * x.
Next, we have "17 more than two-thirds of ...". We have 17 more than the number we just got, so we have 17 more than (2/3) * x = 17 + (2/3) * x = (2/3)*x + 17 as our answer
