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P5 Maths: Stats and Probability: Help needed!


JackRabbit
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Question:

There are 8 white poker chips and 5 black poker chips in a bag.

What is the minimum number of chips to take out (without looking) to be sure that you have one chip of each color?

 

Please explain how to derive the answer - thanks!!

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Question:

There are 8 white poker chips and 5 black poker chips in a bag.

What is the minimum number of chips to take out (without looking) to be sure that you have one chip of each color?

 

Please explain how to derive the answer - thanks!!

 

9 lor.

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MOE using casino as problem question., Training future integrate resort professional..

 

Haha...the teacher who set the question must be a gambling addict.

 

But gambling is about stats and probability.

 

P5 get to learn this so early. Liao...it's the beginning of the end.

Edited by Watwheels
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6 lor. 5 black and 1 white but must be super sway to get all 5 black cos the probability of getting all the black is very low.

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6 lor. 5 black and 1 white but must be super sway to get all 5 black cos the probability of getting all the black is very low.

Pls be reminded he also can be very heng to grabbed all 6 white chips.. Want guarantee, should be 9.

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Pls be reminded he also can be very heng to grabbed all 6 white chips.. Want guarantee, should be 9.

 

[laugh] [laugh] Ya hor. 9 then.

 

Like that almost empty the bag liao. [:p]

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This is a question to test logical thinking rather than any math. Many people tend to lock on to the key word "minimum" and choose 6 as the answer as there are 5 black chips.

 

Not so obvious is the fact that, as Little_prince mentioned, there is a slim possibility that out of the 6 draws, all 6 are white chips!

 

I think P5 math normally don't include this topic, i.e. permutations / probability?? Unless talking about gifted prog math.

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answer liddat, then the answer should be "depends on luck lor". Can be 2 also when heng heng one is black, next is white or vice versa (provided luck is superb).

It's say with out looking. So its 9. Probablity no explanation one. Just a number.
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Question:

There are 8 white poker chips and 5 black poker chips in a bag.

What is the minimum number of chips to take out (without looking) to be sure that you have one chip of each color?

 

Please explain how to derive the answer - thanks!!

 

This is not really a probability question, more like logical thinking.

 

To confirm have a white and a black, need to take out 9 chips and that is the worse case and draw out all the 8 white poker chips before the black chips is taken out.

 

W W W W W W W W B

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not probability, but a test of student analytic or logical analysis lah.

 

it is kind of like if u know the length of a particular pulse is say 10 nm. and a photon maybe considered to be at a point anywhere in this pulse, and the qn ask you for the uncertainty in the position of the photon, the answer wld be juz 10 nm lor.

 

thus u got 8 W n 5 B, min chips drawn such that u got one of each,

 

take the worse case scenario of drawing 8 consecutive white, then only the 9th one confirm will be black,

 

or similarly, the joker drew 5 consecutive black, then only the 6th one will be white.

 

if you tok in terms of probability, of coz the prob of drawing all white b4 kana black is much much lower as compared to that of drawing all black then kana white.

 

but, here the qn is not asking for probability but asking how many minimum balls.

 

So to guarantee 1 white and 1 black, we cannot say for certainty that we will strike all black and then finally 1 white. so the correct answer shld be worst case of suay until lau sai, kana all white b4 1 black. so min chips required is 9.

 

cheers,

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Question:

There are 8 white poker chips and 5 black poker chips in a bag.

What is the minimum number of chips to take out (without looking) to be sure that you have one chip of each color?

 

Please explain how to derive the answer - thanks!!

 

Shouldn't the answer be 2?

 

If question changed to "What is the maximum number of chips..." then it should be 9

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Shouldn't the answer be 2?

 

If question changed to "What is the maximum number of chips..." then it should be 9

You missed out the words "To be sure".

 

2 is no guaratee

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