Since we want just the top 20% applicants and the data is normally distributed, we can use a z-score table to check the z-score that gives this percentage.
The z-score table usually shows the percentage for the values below a certain z-score, but since the whole distribution accounts to 100%, we can do the following.
We want a z* such that:

But, to use a value that is in a z-score table, we do the following:

So, we want a z-score that give a percentage of 80% for the value below it.
Using the z-score table or a z-score calculator, we can see that:
![\begin{gathered} P(zNow that we have the z-score cutoff, we can convert it to the score cutoff by using:[tex]z=\frac{x-\mu}{\sigma}\Longrightarrow x=z\sigma+\mu](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20P%28zNow%20that%20we%20have%20the%20z-score%20cutoff%2C%20we%20can%20convert%20it%20to%20the%20score%20cutoff%20by%20using%3A%5Btex%5Dz%3D%5Cfrac%7Bx-%5Cmu%7D%7B%5Csigma%7D%5CLongrightarrow%20x%3Dz%5Csigma%2B%5Cmu)
Where z is the z-score we have, μ is the mean and σ is the standard deviation, so:

so, the cutoff score is approximately 72.
The slope represents the the number of hours after the sunrise, and the y intercept represents the temperature
The linear function would y=4x+4
6.) y=4+ 10/5x
7.) y= -5 -3x
The first step to do is to calculate first the total
household waste generate for the two years. That is:
total waste generated = 23,400,000 tons + 48,100,000 tons
total waste generated = 71,500,000 tons
Now, to write either a very big number or a very small number
in a form of scientific notation simply means to write it in a decimal form
such as: 12.5 * 10^10
Now to write 71,500,000 in scientific notation, the decimal
form is 7.15, however we still need to find out the * 10^n factor. The value of
n depends on the number of places the decimal point was moved. If the movement
was from right to left, the value of n is positive and if the movement was from
right to left, the value of n is negative. Since the decimal point was moved by
7 places, hence the complete scientific notation is:
7.15 * 10^7 tons
I think the third one on both part a and b can't be used to find the answer