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What is the probability that offspring produced by a mating between Individuals III.j and III.m would be

afflicted with either Disease 1 or Disease 2?

A. 1/4

B. 1/2

C. 3/4

D. 1

So i actually chose C due to the fact that the probability of either of tow events happneing is equal to P1 + P2 - P1*P2

So P of disease ! happening here is = 1/2 becuase only IIIm is carrying the allele for disease I which is dominant. And that of P2 = 1/2 that IIIj will pass its allele * 1/2 that IIIm is a carrier * 1/2 The probability that IIIm will pass its disease two allele. Because the disease 2's allele is recessive. = 1/8

Hence P 1 or 2 = 1/2 + 1/8 - 1/16 = 3/4.

But the answer is B, can someone explain why?

@Next Step Tutor @aldol16 @NextStepTutor_2 @NextStepTutor_3