probability of getting black card an ace =2/52=1/26
-4+x=9.5
x=13.5
The student might have subtracted 9.5-4, which results in the answer 5.5. The correct answer is 13.5.
Answera and Step-by-step explanation: Correlation Coefficient is the measure of how strong two variables are. There are numerous types of correlation coefficients and the product moment correlation coefficient, also known as <em>Pearson's correlation</em> or <em>Pearson's R</em> is most commonly used in linear regression. The formula to calculate it is:
r = n(∑xy) - (∑x)(∑y) / √[∑x² - (∑x)²].[n∑y² - (∑y)²]
To find the value of R:
1) Separate the values of X and Y and out them in 2 columns.
2) Add 3 more columns: for xy, x² and y²;
3) Find the values of each column;
4) Add each column;
5) Put the sum of each column in its place on the formula above;
6) Find the correlation.
i) For this question, r = 0.9645. As it's <u>positive</u>, means that the two variables are directly linked, i.e., an increase in one variable will produce an increase in the other variable in the same proportion.
ii) The Senator should distribute Norvasc to the old adults groups, because, as the <u>population grows</u>, the death associated with high blood pressure will <u>also grow</u>, as explained by the correlation coefficient.
