Answer:
Step-by-step explanation:
Hello!
X: Cholesterol level of a woman aged 30-39. (mg/dl)
This variable has an approximately normal distribution with mean μ= 190.14 mg/dl
1. You need to find the corresponding Z-value that corresponds to the top 9.3% of the distribution, i.e. is the value of the standard normal distribution that has above it 0.093 of the distribution and below it is 0.907, symbolically:
P(Z≥z₀)= 0.093
-*or*-
P(Z≤z₀)= 0.907
Since the Z-table shows accumulative probabilities P(Z<Z₁₋α) I'll work with the second expression:
P(Z≤z₀)= 0.907
Now all you have to do is look for the given probability in the body of the table and reach the margins to obtain the corresponding Z value. The first column gives you the integer and first decimal value and the first row gives you the second decimal value:
z₀= 1.323
2.
Using the Z value from 1., the mean Cholesterol level (μ= 190.14 mg/dl) and the Medical guideline that indicates that 9.3% of the women have levels above 240 mg/dl you can clear the standard deviation of the distribution from the Z-formula:
Z= (X- μ)/δ ~N(0;1)
Z= (X- μ)/δ
Z*δ= X- μ
δ=(X- μ)/Z
δ=(240-190.14)/1.323
δ= 37.687 ≅ 37.7 mg/dl
I hope it helps!
Answer:

Step-by-step explanation:
I did this before. Also sometimes once I look at the question I just find out the answer without steps.
Answer:
i made it going by 2's as it's easier and quicker and more efficient. sorry for the messy hand writing.
A. The term "units" refers to the measurements in the original question or problem. When looking at the question, the units we are measuring are dollars/feet.
B. In this case, the f'(x) means we are looking for the cost (in dollars) to drill the next foot down.
C. Since the cost increases the more feet we drill down, the sign of f'(x) is positive.