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Paging All Junior Mathematicians

The Puzzler


RAY: Now, unencumbered by the thought process as usual, my brother guessed the potatoes would weigh 99 pounds.

TOM: Yeah.

RAY: When I guessed, off the top of my head, I guessed about 90 pounds.

TOM: 'Cause it just feels right.

RAY: Yeah. Now if you do the math, 1 percent of a 100, which is what the potato is, is one pound. As we told you, that's 1 percent. So 2 percent, when its 98 percent water, two percent of the new weight of the mass is still going to be equal to that one pound, and 2 percent of 50 pounds is a pound. So the potato weight is now 50 pounds, not 100.

[ Car Talk Puzzler ]

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