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This puzzle can be done without pencil and paper.

But if you like to doodle, it's allowed. B))

You have two bags.

In one bag there are 4 black balls and 4 white balls.

In the other, there are 4 black balls and 4 white balls.

You take a ball from each of the bags.

What are the chances at least one of the balls you drew is black?

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This puzzle can be done without pencil and paper.

But if you like to doodle, it's allowed. B))

You have two bags.

In one bag there are 4 black balls and 4 white balls.

In the other, there are 4 black balls and 4 white balls.

You take a ball from each of the bags.

What are the chances at least one of the balls you drew is black?

50/50

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To get at least one black, assume Bag (A) and Bag (B)

BK (A) & WH (B) or BK (A) & BK (B) or WH(A) & BK (B)

=(4/8)*(4/8) + (4/8)*(4/8) + (4/8)*(4/8)

= 3 * (1/4)

= 3/4

the chance is 75% ?

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To get at least one black, assume Bag (A) and Bag (B)

BK (A) & WH (B) or BK (A) & BK (B) or WH(A) & BK (B)

=(4/8)*(4/8) + (4/8)*(4/8) + (4/8)*(4/8)

= 3 * (1/4)

= 3/4

the chance is 75% ?

There is a 25% chance of white being picked

If the OP had said white - would it be 75%?

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This puzzle can be done without pencil and paper.

But if you like to doodle, it's allowed. B))

You have two bags.

In one bag there are 4 black balls and 4 white balls.

In the other, there are 4 black balls and 4 white balls.

You take a ball from each of the bags.

What are the chances at least one of the balls you drew is black?

I think

P(one black)=P(WB)+P(BW)+P(BB)=(1/2)(1/2)+(1/2)(1/2)+(1/2)(1/2)=3/4

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So there is a 25% chance of white being picked

If the OP had said white - would it be 75%?

yes. Because it's "at least one", so the chances aren't 50/50, though the chances are the same for white and black

think of it this way:

Black - Black

White - White

White - Black

Black - White

all of those, except for 1, have a black included. So it's 3/4. White would also be 3/4, if it was asked of white. It's easy once you see that the probability to get all black is 1/4, all white is 1/4, and one of each is 1/2

:P

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This puzzle can be done without pencil and paper.

But if you like to doodle, it's allowed. B))

...

What are the chances at least one of the balls you drew is black?

I doodled a black ball on the paper, so the chances I drew a black one is 100%!

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yes. Because it's "at least one", so the chances aren't 50/50, though the chances are the same for white and black

think of it this way:

Black - Black

White - White

White - Black

Black - White

all of those, except for 1, have a black included. So it's 3/4. White would also be 3/4, if it was asked of white. It's easy once you see that the probability to get all black is 1/4, all white is 1/4, and one of each is 1/2

:P

except for one is black, except for one is white logic says it can't be 75% of the one you want (murphy's law). I'll open the betting and take the odds that you all seem to think a black is gonna be first. But as I will draw first hoping it;s white then I'll have a 75% chance of winning B)) cool and rich in no time

I like the doodle answers ***** for GIJeff

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Heh heh ... look again, there's a white ball right next to it.

Wait.

The paper is white.

You can't see it.

But it's there. :)

but still...at least one of the ones I drew was black :D

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You're absolutely right.

And I thought of that as I posted.

But my silliness still seemed worth publishing [iMHO] ... :P

When Puzzle Grandmasters are silly they're clever.

When others are silly they get warned.

Because those are the rules... :P

hahaha, because he who makes the rules rules.

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yes. Because it's "at least one", so the chances aren't 50/50, though the chances are the same for white and black

think of it this way:

Black - Black

White - White

White - Black

Black - White

all of those, except for 1, have a black included. So it's 3/4. White would also be 3/4, if it was asked of white. It's easy once you see that the probability to get all black is 1/4, all white is 1/4, and one of each is 1/2

:P

Thanks for Unreality for answering on my behalf. :)

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