It's not the one given where I saw this posted, but I can't reconcile the difference. Another way of saying your answer is that there is a 50% chance I will pick the croaker and be cured, and a 50% chance I will pick the toad that did not croak, and a 50% chance that one will be male and I am cured, so .5 + .5*.5 = 75%. I can't find fault with that.
The other analysis says there are two toads, one on the left (capitalized) and one on the right (lower case). The equally probable arrangements of those toads are:
But the fact that one of them croaked tells us that Ff is not the case. Then we are left with three cases, and whether you pick the one on the left or the one on right, there is a 2/3 chance it is male.
There is a very subtle flaw in one of these reasonings, and I'll be darned if I can find it.