Answer:
and 
this is what i think, hope it helps
You only need to consider the situations where 10 or 11 of the babies are girls, then subtract those probabilities from 1. This will give probability that any other number up to 9 of the babies are girls.
Use binomial theorem.

n = 11
k = 10,11
p = 1/2
Answer: 1-27 2-8 3-9 4-32
Step-by-step explanation:
Answer:
(-oo, -8/3) U (-8/3, oo)
Step-by-step explanation:
Hope this helps.
The percent of students that are aged 19 years or more is determined as 84%.
<h3>One standard deviation below the mean</h3>
In a normal distribution curve 1 standard deviation below the mean is defined as follows;
- 1 std below mean : M - d = 16%
M - d = 20.6 yrs - 1.3 yrs = 19.3 years ≈ 19 years
19 years or more will occur at (M - d) + (M) + (M + 2d) = 100% - (M - d)
= 100% - 16%
= 84%
Thus, the percent of students that are aged 19 years or more is determined as 84%.
Learn more about normal distribution here: brainly.com/question/4079902
#SPJ1