re: Strange-But-True Mathematical brain teasers

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Wouldn't your new radius be +2?

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Diameter would increase +2.

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Y'all are nerds

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If they started the game at noon, we wouldn't have this problem.

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Strange-But-True Mathematical brain teasers

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eta:

Oh ok, now I see after reading your second post why it is "strange but true"

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I wouldnt call it "strange but true" or a "brain teaser"

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Many people would disagree with you. Separating a constant equation from the scale of the objects involved stymies more than a few.

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I got 75.36 in for the second one

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Also correct. As they say in Da Parish, "It's the same thing, but different".

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Everyone except one person keeps answering 2pi feet longer for question 1. It should be 2pi miles longer, right?

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No. I didn't specify feet, soy ou can answer it in any unit of measure you wish. Feet is the most common.

6.28 feet
75.4 inches
0.00118999722 miles

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25006

Sphere:
C=2pir
25000= 2(3.14)r
r=3980 and change
3980+1 = new radius
3981(2)3.14= 25006.2

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This answer would be 6.28 MILES

If you wanted to use the radius of each (and not the simpler of just the difference) then you'd have to change miles to feet. It would then read like this:

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Sphere:
C=2pir
132,000,000= 2(3.14)r
r= 21,008,452and change
21,008,452+1 = new radius
21,008,453(2)3.14= 132,000,006.28

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You have a smooth sphere as big as a basketball (30 inches in circumference).

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You have 2 pieces of string. String 1 is 30 inches long and wraps around the sphere at the equator, touching the surface all the way. String 2 is also all the way around at the equator, except String 2 sits 1 foot off the surface all the way around

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We talking basketballs or equators?

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quote:
25006

Sphere:
C=2pir
25000= 2(3.14)r
r=3980 and change
3980+1 = new radius
3981(2)3.14= 25006.2

This answer would be 6.28 MILES

If you wanted to use the radius of each (and not the simpler of just the difference) then you'd have to change miles to feet. It would then read like this:
quote:

Sphere:
C=2pir
132,000,000= 2(3.14)r
r= 21,008,452and change
21,008,452+1 = new radius
21,008,453(2)3.14= 132,000,006.28

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No. You're mixing units of measurements. Convert everything to miles or feet and stick with one throughout the entire problem.