A chicken math question

[Sunny Side Up]

Let's say you have 10 Red Sex-Link eggs developing nicely in your incubator. The day comes when they all begin to hatch. You watch them as they push themselves out, and you can tell by their color what sex they are.

The first five are completely out and drying off, you know for certain by their reddish fluff they are pullets. Now the sixth one is pushing out.

What sex do you think it might be? What do you think are its chances of being a cockerel? What about the last 4?

 

[milleryardchx]

I have heard you normaly should have 2 cockerels for every 10 but thats never worked for me. My last batch of our farm eggs had 6 eggs all but 1 were cockerels then I have hatched shipped eggs and all were pullets except 2. bottom line i think its all a luck of the draw of what eggs you pick up and put in the incubator that day.

 

[Junkmanme]

Assuming that the average is 50% each for pullets or cockerels, then EACH EGG has a 50-50 probability.
The fact that the first five to hatch were pullets has NO BEARING on the probability of further hatches.

-Junkmanme-

 

[HEChicken]

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The 2 cockerels for every 10 sounds more like the ration of roos/hens (although I usually hear 1:10 for that). I don't see why the ratio of pullets/cockerels at hatch wouldn't be 50:50 just like any other breed so.....Sunny_Side_Up, sounds like you've been lucky so far. My engineer DH would give you a probability of numbers 6, 7, 8, 9, 10 being pullets but I'll just keep my fingers crossed for you.

 

[HEChicken]

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Oh yeah, I remember that now from math class! So Sunny, I predict the probability that number 6 will also be a girl is 50%!

 

[Sunny Side Up]

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Go to the Head of the Class, Junkmanme! That is correct!

I was given a similar question in college botany class & it stumped us too. It's like flipping a coin. Each toss has a 50-50 chance of landing on a chosen side. Even if your coin has landed on "heads" 5X in a row, the next toss still has a 50% chance of being "tails".

 

[Ban seabhag]

Quote:
Absolutely. The "odds" figure over a period of time to average out, but each time is a 50-50 chance. ( i.e. you don't have to make 99 tries before the 1 in a hundred chance comes through,,...then again, you might.

 

[pips&peeps]

I was under the impression that it was 51% male, 49% female. Don't remember where I read it.