## Friday, October 2, 2009

You are making a bean soup. You put 1 cup of beans, 3 cups of water and starting to boil the pot. The package says that beans will grow 2 times in diameter by the time they are ready. Your soup already takes two thirds the pot. Will it overflow?

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Alin Grin said...

no 0.33>0.25

Maria said...

What does 0.33 and 0.25 has to do with our beans?

Alin Grin said...

The beans absorbs the water in the pot so the water level will stay the same.

Alin Grin said...

Maria said...

Brilliant!

The beans will expand by absorbing water, so the overall level of the soup should not change.

But we may need more water...
If beans are growing twice in diameter, their volume is growing 2 x 2 x 2 = 8 times! 1 cup of dry beans will produce 8 cups of soup. For a full expansion we will need much more water (7 cups total) and a larger pot. Our pot is 2/3 full with 4 cups in it, so it could contain only 6 cups.

But if we won't add water, it won't be able to expand fully, leaving the soup level the same.
Home chefs, do you agree with Alin and me?