Answer:
<em>There is a </em><em>7.67%</em><em> chance of getting exactly 43 boys in 90 births.</em>
Step-by-step explanation:
Hint- We have to calculate mean(μ) and standard deviation(σ) from binomial distribution and then calculate the z score for normal distribution. After then we can get the probability.
For Binomial distribution,
n = sample size = 90
p = probability of event of getting a boy = 0.5 (as we have only two choices, boy and girl)
Putting these in the formulae,
Now we have to convert the z-values using the continuity correction as the binomial is a discrete distribution. Because as in the question the probability of getting exactly 43 boys in 90 births is asked. Number of boys can not be in fraction, so it is discrete.
In normal distribution,
So,
Using the standard normal table,