2=6
4=8
6=10
8=12
I added +4 for each
18 girls
Half of the students volunteer
15 don't -- so the other half must be 15 as well making there 30 students in the class.
If 12 are boys, then 30(students in class) - 12 (boys) = 18 girls
Answer:
The 90% confidence interval for the population proportion who knew about the incentives is (0.28, 0.44).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
For this problem, we have that:

90% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 90% confidence interval for the population proportion who knew about the incentives is (0.28, 0.44).
Answer:
number of units for cost to be minimum=150
Step-by-step explanation:
y=2x^2-600 x+49000
dy/dx=4x-600
dy/dx=0 gives 4x-600=0
4x=600
x=150
d^2y/dx^2=4x
at x=150,d^2y/dx^2=4*150=600>0
so y is minimum at x=150