it is true that PXP earned 2.34/share. (That's a PXP share). However, PXP has 1/10 the share count of FCX. So when PXP is folded into FCX, that will contribute $230m, which is 23c per FCX share. annually.
That is still accretive to FCX, since interest payments to buy out PXP are likely less than that. And eventually, in a few years when that debt is paid off, and PXP and MMR contribute much more profit to FCX, the value of the transaction will be very obvious.