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# Giant Jelly

## Question

A giant jelly weighs 100 pounds and is 99% water by weight.

It is set out in the sun and water evaporates until it is 98% water by weight.

How much does the jelly now weigh?

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50 pounds

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roughly 50 pounds.

more precisely, x/(x+1) = .98

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It would seem that the answer 50 given by vistaptb is exactly correct, not approximately correct. Because there is exactly one pound of non-water then this with exactly 49 pounds of water gives 50 pounds total with 98 percent water. If x is the total weight then the correct equation is (x-1)/x = 0.98

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That taking away one measly percentage point in the water proportion corresponds to losing 50 pounds of water?

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That will be correct, right ?

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That taking away one measly percentage point in the water proportion corresponds to losing 50 pounds of water?

I know right? It seems quite odd and slightly unbelievable, but, as I'm sure you know, since the water makes up such a large portion of the total mass 1% less is a significant change.

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That will be correct, right ?

Yup!

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There was 99 pounds of water in 100 pounds Jelly. Say X pound giant jelly is left after evaporation, which now contain 98%water. Balance 2% is jelly which will remain to be 1 pound as originally it was. So 2X/100 = 1 OR X = 50 Pounds.

Therefore Giant gelly now weighs 50 Pounds.

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It weighs 99 pounds, the jelly doesn't evaporate? Maybe?

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when 100 pounds of jelly has 99% of water, and the water decreased into 98%, then maybe the jelly will weigh 99 pounds.

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krizhelle.. wat??!!

and by the way.... very good puzzle mmiguel... seemed very simple at first ... but took me half an hour and 2 pages full of writing equations with "x" in it..

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Yes, i get it now

slightly under 50 pounds

The jelly doesn't evaporate

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