In the puzzler, it was revealed that Wurme could only dig up a 12-oz bottle of 60% lemon extract and a pitcher of 7% (by volume) lemonade.

What was the final lemon concentration of the mixture if he added equal parts?

Also:  How much lemonade would he have needed to get the 12 oz of extract to the desired (15%) level?

The lemon concentration (see the worked-out solution on the left) is rc = 33.5%.

He would have needed 67.5 oz to get the extract to a drinkable level.

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