Topscore test 3 Question 34
- Thread starter Doctor PJ
- Start date
I would say between 1 and 2 (really 1.5 but thats not possible).
Sure! This one is definitely a bit confusing. Here we go:
Since this causes spontaneous abortions, any man that got the trait would die. obviously the Father doesnt have it. The problem tells you the Mom is a carrier. Basically, since the father cannot have the trait, NONE of the girls will have it.
Now for the boys, each boy has a 50/50 chance of getting the X w/ the trait from the mother. So, 1/2 of her boys will have it and die and the other half will survive. You also know that the chances of having a boy is 1/2 which is the same for girls.
so you know she will have half boys and half girls. additionally, half the boys will die from the disease. so out of the 6 kids, the boys only represent 1/4 of the LIVE kids (1/2 boys * 1/2 boys lived). then half of the original babies were girls. so the 6 children represent (1/2 + 1/4 = 3/4) 75 % of all her kids. so 6 * 4/3 = 8 total kids.
1/4 are live boys so she has 2 boys and 6 girls.... 👍
LMAO if it said that she had 8 children it woulda made sense but the question reads that she has 6 children. Therfore the answer is 1.5 The answer 2 is only correct if it would say 8 children. The way to do it is 1/2 posibility that its a boy and 1/2 possibility that the boy dies so 1/2*1/2*6=1.5 Thats impossible so i dunno.
Naw son, it says she HAS 6 children... in the present. If it said she HAD 6 children you would be correct. Tricky, I know. But they want you to assume she HAD some children that she doesnt HAVE right now. So my answer should be correct.
What are you kidding me. I read the question as she has 6 children in her lifetime LOL that question is so poorly written.
ya i know its horribly written, but the answer couldnt be 1.5. stupid question.
No thats wrong, if she had only 6 children in her entire life, then she had 1.5 boy that lived, 1.5 boys that died, and 3 girls that lived.
I agree with Klutzy. 1.5 boys =)
chance of having a boy = 1/2, chance of the boy surviving if the disorder is leathal = 1/2
if she has 6 kids the probability of having a normal boy is 1/2 x 1/2 x 6 = 1.5
between 1 and 2.
chance of having a boy = 1/2, chance of the boy surviving if the disorder is leathal = 1/2
if she has 6 kids the probability of having a normal boy is 1/2 x 1/2 x 6 = 1.5
between 1 and 2.
Thats what i thought, but thats rediculous, you can not have 1.5 boys would the answer be 1 or 2. What a dumb question.
