Buying in bulk to save money seems like a good idea, but in practice it doesn’t work so well. Want proof? Check out these examples of unit prices that go up the more you buy. We call it Target Math, since the phenomenon happens often in Target stores. Not exclusively in Target stores, though, as you will see.

Reader Wilman sent us this photo from his local Walmart. I was unaware that orange juice came in shrink-wrapped two-packs. That seems very handy, but not when you have to pay 28¢ more for the same quantity.

Maybe that shrink-wrapping is worth an extra 28¢ to some consumers. Whatever they’re into, we guess.

Meanwhile, over at Wegmans, Max has something to clean all of that orange juice acid out of our mouths. Except not.

In this case, there are two different bottle sizes in the mix, possibly making matters even more confusing. Still, you can sort things out with some elementary school level math.

“If you don’t believe the unit price,” Max points out, 6L of the one on the left is four bottles for $27.96, while 6L of the item on the right is 6 bottles, or 3 x $9.49, or $28.47.”

Well…at least the unit prices are calculated correctly? Here’s a zoomed-in version of those shelf tags from Wegmans.

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