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Puzzle Details

If a bottle weighs eight ounces plus half a bottle, what is the weight of a bottle and a half?

Answer: 24 ounces: the bottle weighs 16 ounces.

As a bottle weighs eight ounces plus half a bottle we can write this as:

B = 8 + ½B

Take ½ from both sides to get:

½B = 8

So B = 16, which means B + ½B = 24.

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