Awuah29

Christian predent
7+ Year Member
15+ Year Member
Oct 13, 2003
294
0
New Jersey
Status (Visible)
Guys, why are 50% of the daughters colorblind. I came up with 25%. Maybe I am missing something here. :confused:

Let see C= normal vision
c =colorblind

using the punnett square

Xc Y
XC XC Xc XC Y

Xc Xc Xc Xc Y

First girl carrier = normal 25%
Second girl = colorblind 25%
 

slashnroses19

Full Member
10+ Year Member
Sep 4, 2006
178
7
Status (Visible)
  1. Dental Student
you did the punnett square correctly but you didn't interpret the results correctly. one daughter is color blind and the other one is a carrier. So, half the daughters are colorblind. The answer would be 25% if they asked the probability of their first CHILD being a colorblind daughter. check out the other punnett square problems, you'll see what i mean.
 

Awuah29

Christian predent
7+ Year Member
15+ Year Member
Oct 13, 2003
294
0
New Jersey
Status (Visible)
you did the punnett square correctly but you didn't interpret the results correctly. one daughter is color blind and the other one is a carrier. So, half the daughters are colorblind. The answer would be 25% if they asked the probability of their first CHILD being a colorblind daughter. check out the other punnett square problems, you'll see what i mean.

wait a minute, why is half the daughters colorblind . One is carrier Cc (normal)
and the other one is cc colorblind . I understand with the probability scenario, but how do we get half of the daughters colorblind.


ok, gonna give jim and nancy a call:love:
 

Streetwolf

Ultra Senior Member
10+ Year Member
7+ Year Member
Oct 25, 2006
1,801
7
NJ
Status (Visible)
  1. Dentist
Because the other 2 children in your square are SONS and the question asks about DAUGHTERS!

It wants to know the % of colorblind DAUGHTERS not children. So you only look at the two daughters. Of the two daughters, one is colorblind. 1 out of 2 = 50%.
 
About the Ads

dantheman2007

Full Member
10+ Year Member
Jan 12, 2007
501
0
Status (Visible)
one daughter is colorblind, one is a carrier
so the probability of a daughter being color blind is one half or 50%
that is all there is to it.
 

markimark

Full Member
10+ Year Member
7+ Year Member
Apr 29, 2006
27
0
Boston
Status (Visible)
  1. Dental Student
50% of the DAUGHTERS will be colorblind; that is, 25% of ALL THE KIDS will be colorblind.

watch out for the wording and what you're being asked.
 
This thread is more than 14 years old.

Your message may be considered spam for the following reasons:

  1. Your new thread title is very short, and likely is unhelpful.
  2. Your reply is very short and likely does not add anything to the thread.
  3. Your reply is very long and likely does not add anything to the thread.
  4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
  5. Your message is mostly quotes or spoilers.
  6. Your reply has occurred very quickly after a previous reply and likely does not add anything to the thread.
  7. This thread is locked.