Students took two parts of a test, each worth 50 points. Part A has a variance of 25, and Part B has a variance of 36. The correlation between the test scores is 0.8. (a) If the teacher adds the grades of the two parts together to form a final test grade, what would the variance of the final test grades be? (b) What would the variance of Part A - Part B be?

Following are the solution to the given choices:

Step-by-step explanation:

In point a:

Calculating the variance of the test grade:

In point b:

The relationship between the top 20 students is also slight, so the top 20 students are more university-like than all secondary students.

wholesale price is the initial price before markup. retail price comes after the markup.

a price of 8 bucks that's marked up by 100%   is

formula: initial price + (percent markup in fraction/decimal)(initial price)

8+(1)(8)

8+8

16

retail price is $16.

probably the last option

step-by-step explanation: