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.
Here we are given the specific equation of:
amount of eroded soil = 0.4 + 1.3 x
where x is the flow rate
A linear equation has a general formula in the form of:
y = m x + b
where m is the slope and b is the y intercept of the equation
If we compare this with our specific equation, we can see that the slope and y intercept are both positive with values:
m = 0.4
b = 1.3
Therefore this only means that as the flow rate increases, the amount of eroded soil also increases.
Hence the correlation must be positive but we cannot solve for the exact value since we need the data for x and y.
Answer:
positive, but we cannot say what the exact value is
Answer:
18
Step-by-step explanation:
90% of 20 is 18
Answer:
1. 1
2. 40
3. 36
Step-by-step explanation:
brainliest?
For this you can write equations for your business and your friend's. For your's it would be y=10x-25 and for your friend's it would be y=13x-55. Now at this point you can just plug in numbers until you match up. Your answer would be 10, if you want to you can plug it in to check.
