Step-by-step explanation:
a. First, find the z-score.
z = (x − μ) / σ
z = (80 − 74.0) / 12.5
z = 0.48
Use a calculator or table to find the probability.
P(z < 0.48) = 0.6844
b. Find the standard deviation of the sample.
σₓ = σ / √n
σₓ = 12.5 / √4
σₓ = 6.25
Find the z-score.
z = (x − μ) / σ
z = (80 − 74.0) / 6.25
z = 0.96
Use a calculator or table to find the probability.
P(z < 0.96) = 0.8315
c. When the distribution of the population is normal, then the distribution of the sample mean is also normal.
The answer is 30,000
20,100 / 0.67 = 30,000
Answer:
C I’m not sure tho
Step-by-step explanation:
So the first question you just need to convert it to its simplest form. You would do 105 \ 20 and that turns into 4 5/20.
The second question is turning it into a improper fraction so instead of dividing it you would multiply the whole number with the denominator, then add the numerator. So 4 x 9 = 36.
36 + 8 = 44
Add back the denominator to 44 and you get
44/9
