Answer:
The probability that a call last between 4.2 and 4.9 minutes is 0.4599
Step-by-step explanation:
Let X be the length in minutes of a random phone call. X is a normal distribution with mean λ=4.2 and standard deviation σ=0.4. We want to know P(4.2 < X < 4.9). In order to make computations, we will use W, the standarization of X, given by the following formula

We will use
, the cummulative distribution function of W. The values of
are well known and the can be found in the attached file

We conclude that the probability that a call last between 4.2 and 4.9 minutes is 0.4599
Giving the table below which shows <span>the percent increase of donations made on behalf of a non-profit organization for the period of 1984 to 2003.
</span>
Year: 1984 1989 1993 1997 2001 2003
Percent: 7.8 16.3 26.2 38.9 49.2 62.1
The scatter plot of the data is attached with the x-axis representing the number of years after 1980 and the y-axis representing the percent increase <span>of donations made on behalf of a non-profit organization.
To find the equation for the line of regression where </span><span>the x-axis representing the number of years after 1980 and the y-axis representing the percent increase of donations made on behalf of a non-profit organization.
![\begin{center} \begin{tabular}{ c| c| c| c| } x & y & x^2 & xy \\ [1ex] 4 & 7.8 & 16 & 31.2 \\ 9 & 16.3 & 81 & 146.7 \\ 13 & 26.2 & 169 & 340.6 \\ 17 & 38.9 & 289 & 661.3 \\ 21 & 49.2 & 441 & 1,033.2 \\ 23 & 62.1 & 529 & 1,428.3 \\ [1ex] \Sigma x=87 & \Sigma y=200.5 & \Sigma x^2=1,525 & \Sigma xy=3,641.3 \end{tabular} \end{center}](https://tex.z-dn.net/?f=%5Cbegin%7Bcenter%7D%0A%5Cbegin%7Btabular%7D%7B%20c%7C%20c%7C%20c%7C%20c%7C%20%7D%0A%20x%20%26%20y%20%26%20x%5E2%20%26%20xy%20%5C%5C%20%5B1ex%5D%20%0A%204%20%26%207.8%20%26%2016%20%26%2031.2%20%5C%5C%20%20%0A%209%20%26%2016.3%20%26%2081%20%26%20146.7%20%5C%5C%20%0A13%20%26%2026.2%20%26%20169%20%26%20340.6%20%5C%5C%20%0A17%20%26%2038.9%20%26%20289%20%26%20661.3%20%5C%5C%20%0A21%20%26%2049.2%20%26%20441%20%26%201%2C033.2%20%5C%5C%20%0A23%20%26%2062.1%20%26%20529%20%26%201%2C428.3%20%5C%5C%20%5B1ex%5D%0A%5CSigma%20x%3D87%20%26%20%5CSigma%20y%3D200.5%20%26%20%5CSigma%20x%5E2%3D1%2C525%20%26%20%5CSigma%20xy%3D3%2C641.3%20%20%0A%5Cend%7Btabular%7D%0A%5Cend%7Bcenter%7D)
</span>
Recall that the equation of the regression line is given by

where

and

Thus, the equation of the regresson line is given by

The graph of the regression line is attached.
Using the equation, we can predict the percent donated in the year 2015. Recall that 2015 is 35 years after 1980. Thus x = 35.
The percent donated in the year 2015 is given by

Therefore, the percent donated in the year 2015 is predicted to be 90.5
Answer:
Gemma gets 3 biscuits
Zak gets 18 biscuits
Step-by-step explanation:
1:6 = 1+6
= 7
1/7 * 21 = 3
6/7 * 21 = 18
4.27x10*6
i cant get it to come up properly but its to the power of 6
= <u>187.3 yards</u>
Step-by-step explanation:
The set-up will represent a triangle whereby the :
- Width = Height = 150 yards
- Diagonal = Hypotenuse = 240 yards
- Length = Base = ?
