a) Probability of both being males is 27%
b) Probability of both being females is 23%
c) Probability of having exactly one male and one female is 50%
Step-by-step explanation:
a)
The probability that the birth is a male can be written as
(which corresponds to 52%)
While the probability that the birth is a female can be written as
(which corresponds to 48%)
Here we want to calculate the probability that over 2 births, both are male. Since the two births are two independent events (the probability of the 2nd to be a male does not depend on the fact that the 1st one is a male), then the probability of both being males is given by the product of the individual probabilities:
![p(mm)=p(m)\cdot p(m)](https://tex.z-dn.net/?f=p%28mm%29%3Dp%28m%29%5Ccdot%20p%28m%29)
And substituting, we find
![p(mm)=0.52\cdot 0.52 = 0.27](https://tex.z-dn.net/?f=p%28mm%29%3D0.52%5Ccdot%200.52%20%3D%200.27)
So, 27%.
b)
In this case, we want to find the probability that both children are female, so the probability
![p(ff)](https://tex.z-dn.net/?f=p%28ff%29)
As in the previous case, the probability of the 2nd child to be a female is independent from whether the 1st one is a male or a female: therefore, we can apply the rule for independent events, and this means that the probability that both children are females is the product of the individual probability of a child being a female:
![p(ff)=p(f)\cdot p(f)](https://tex.z-dn.net/?f=p%28ff%29%3Dp%28f%29%5Ccdot%20p%28f%29)
And substituting
![p(f)=0.48](https://tex.z-dn.net/?f=p%28f%29%3D0.48)
We find:
![p(ff)=0.48\cdot 0.48=0.23](https://tex.z-dn.net/?f=p%28ff%29%3D0.48%5Ccdot%200.48%3D0.23)
Which means 23%.
c)
In this case, we want to find the probability they have exactly one male and exactly one female child. This is given by the sum of two probabilities:
- The probability that 1st child is a male and 2nd child is a female, namely ![p(mf)](https://tex.z-dn.net/?f=p%28mf%29)
- The probability that 1st child is a female and 2nd child is a male, namely ![p(fm)](https://tex.z-dn.net/?f=p%28fm%29)
So, this probability is
![p(mf Ufm)=p(mf)+p(fm)](https://tex.z-dn.net/?f=p%28mf%20Ufm%29%3Dp%28mf%29%2Bp%28fm%29)
We have:
![p(mf)=p(m)\cdot p(f)=0.52\cdot 0.48=0.25](https://tex.z-dn.net/?f=p%28mf%29%3Dp%28m%29%5Ccdot%20p%28f%29%3D0.52%5Ccdot%200.48%3D0.25)
![p(fm)=p(f)\cdot p(m)=0.48\cdot 0.52=0.25](https://tex.z-dn.net/?f=p%28fm%29%3Dp%28f%29%5Ccdot%20p%28m%29%3D0.48%5Ccdot%200.52%3D0.25)
Therefore, this probability is
![p(mfUfm)=0.25+0.25=0.50](https://tex.z-dn.net/?f=p%28mfUfm%29%3D0.25%2B0.25%3D0.50)
So, 50%.
Learn more about probabilities:
brainly.com/question/5751004
brainly.com/question/6649771
brainly.com/question/8799684
brainly.com/question/7888686
#LearnwithBrainly