a scientist observes a congenital birth defect in a breed of cats and predicts that in a cross between heterozygotes, 25% of the kittens will be born with the birth defect. she surveys several litters, and finds that 44 out of 128 kittens have the defect. to see if her hypothesis is correct, she decides to use chi-square analysis and determines that the expected number of unaffected kittens should be:



Answer :

The expected number of unaffected kittens should be 84

Find the below calculation of chi square:

Category   Affected Unaffected Total

Observed values   44                 84                 128

Expected Ratio         1                  3                   4

Expected Values, E  32             96

Deviation, D              12              -12

Deviation Squared     14            144

D^2/E                           4.5      1.5                  6

X^2                               6  

Degrees of freedom                       -                  1

Unaffected number of kittens:

Observed values for Affected=44

Total=128

25% of the 128 are affected.

The unaffected proportion is,

Total-Observed values for Affected kittens

=128-44

=84

Learn more about Chi-square here:

https://brainly.com/question/4543358

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