1) 450g. 90% of 500 is 450,meaning the pickle itself has a mass of 50g(grams measures mass,not wieght by the way). and 80% of 500 is 400,so 400+50=450g.

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WK and Ace and tuco for scorps.

1. 500gx.9 = 450 g of water. meaning mass of cucumber without water is 50 grams.
x/(50+x) = .8 (80%)
solve for x, you get x = 200 g
total mass of cucumber is 50 g + 200 g = 250 g

2. the moderator opened door B because there was nothing behind door A. so the contestant should choose door C.

i am confident about my math, not so sure about the show contest question.

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i no need thanks, just send money.

your math is wrong,i dunno where you got x,this is not a variable equation,you dont need an x. and think about it logically,it dropped 10% in water so it dropped 50% in mass? that makes no sense. if it dropped 30% in water then it would have negative mass.

your mistake was that you overlooked the fact that its still 80% of 500g.

2) ok,im thinking he should go A again for two reasons,the guy might open C for him,though you didnt explain the riddle very well i dont know if he was supposed to open the wrong door or what. but the second reason is becaus ethe guy at first avoided opening A and giving the prize.

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WK and Ace and tuco for scorps.

penguin, when it comes to math me>you
x = mass of water
try 200/(200+50), it'll give you .8, meaning the mass of water is 80% of the total mass.
i am asian... getting anything below a 90 on a math test is utter shame.

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i no need thanks, just send money.

250 g and the explanation by tsukehane are correct. 450 g would have been a little too obvious for a "riddle".

#2 is a probability thing, the explanation doesn't involve any complicated calculations just try to figure out which different possibilities there are. what i didn't point out specifically is that the moderator will always open 1 door with nothing behind independent from what's behind the door the candidate chose.

normally i'd take that as an insult but i have come to learn u cant help but insult people,and asians do pwn in math so i'm gonna accet that.

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WK and Ace and tuco for scorps.

penguin you asshole... i am not flattered at all... really...

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i no need thanks, just send money.

the questions stand if the contestant should reconsider her/his initial pick or not and why. after all if theres nothing beind B theres still 50/50 chance right? ;)

oooh,got it.
2) the contestant should pick door B so the moderator opens a different door.

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WK and Ace and tuco for scorps.

nooo, its game theory.

riddle number two is one of the basic questions in game theory. Its always better to switch, as the initial door still has the 1/3 chance of being right, but with door B revealed to have nothing behind, door C now has a 2/3 chance of being the right one. If you alwasys switch, you will be better off.

Can't remember the exact explanation.

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Spam Co-Ordinator (retired)

Im still stuck on the damn cucumber... its impossible that it would loose half its weight from loosing only 10% water.
But you seem to know what you´re doing there Tsukhane so instead of arguing im gonna do this:

The same question as before only this time the cucumber looses 30% water.
Can you plz calculate the weight now?

im not trying to mess with you its just that im usually good math and i cant get your explanation to work for me
(might be cuz i just woke up tho..)

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Always outnumbered, never outgunned!

his maths works fine. and if you then use 70%, you will get the mass of water as being 116.7g using the same method.

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Spam Co-Ordinator (retired)

i still dont get it, it says clearly in the riddle that the water weighs 450g So i dont get how 10% could be 200g.

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Always outnumbered, never outgunned!

the water weighs 450g initially. However, when left out in the sun, water will evaporate. Now you had to calculate the mass of the water left when the cucumber's mass is 80% water.

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Spam Co-Ordinator (retired)

One way to look at it is.

Lets say you are thinking door A is right, and you deliberately choose a different door.

Host opens up door either door B or C

You now have a 50% chance at seeing if A is correct or not.

However this is a really good riddle in taht its very hard to grasp the explaination...

The whole idea that the previous probability result should not effect the current one, or the next one, is hammered into our head so hard :p
(If i got 10 heads in a row tossing a coin, wats the chance of head for next one)....