# Chi squared and expected values. Help please :/ watch

1. Hi guys!

I need a little help finding the expectedvalues on my table. This is about genetics, by the way.

I know the expected ratio is 11 and the observed values are as follows:

Red - 62
Pink - 131
White - 67

And the total is 260, of course. I've been searching it everywhere and I must be really stupid because my classmate said it was easy to find :/ and I can't ask my teacher because we're supposed to give it to him as part of our coursework.

Thanks TSR!
2. So you do like a mean for the expected values but to fit your ratio.
It would be 260/4= 65 Then you multiply by your ratio so would be 6565
3. (Original post by katyness)
Hi guys!

I need a little help finding the expectedvalues on my table. This is about genetics, by the way.

I know the expected ratio is 11 and the observed values are as follows:

Red - 62
Pink - 131
White - 67

And the total is 260, of course. I've been searching it everywhere and I must be really stupid because my classmate said it was easy to find :/ and I can't ask my teacher because we're supposed to give it to him as part of our coursework.

Thanks TSR!
I'm assuming that ratio was 1 : 2 : 1?

You have 260 in total.

1 + 2 + 1 = 4 .... your ratio is split into 4 bits.
So divide it by 4 to get 65, to get the value of each 'bit'

A ratio of 1 means 1 x 65 = 65
A ratio of 2 means 2 x 65 = 130

Therefore if you have 260 seeds in the ration 1 : 2 : 1, then you expect to get 65 : 130 : 65 seeds.

4. (Original post by Consilio Et Animis)
So you do like a mean for the expected values but to fit your ratio.
It would be 260/4= 65 Then you multiply by your ratio so would be 6565

(Original post by CityOfMyHeart)
I'm assuming that ratio was 1 : 2 : 1?

You have 260 in total.

1 + 2 + 1 = 4 .... your ratio is split into 4 bits.
So divide it by 4 to get 65, to get the value of each 'bit'

A ratio of 1 means 1 x 65 = 65
A ratio of 2 means 2 x 65 = 130

Therefore if you have 260 seeds in the ration 1 : 2 : 1, then you expect to get 65 : 130 : 65 seeds.

Thank you very much
5. (Original post by katyness)
Thank you very much
No problemo

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Updated: December 12, 2010
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