Question

1. study questions and problems #10

suppose that your chemistry and economics professors have decided to give tests two days from now and you can spend a total of only 12 hours studying for both exams. after some thought, you conclude that dividing your study time equally between the two subjects will give you an expected grade of c in each course. for each additional three hours of study time for one of the subjects, your grade will increase one letter for that subject, and your grade will fall one letter for the other subject.
in the following table, calculate the hours for the \hours of study on chemistry\ column. then fill in the \expected grade in economics\ and the \expected grade in chemistry\ columns.
hours of study on economics hours of study on chemistry expected grade in economics expected grade in chemistry
12
9
6
3
0

Explanation:

Step1: Total study - time is 12 hours

The sum of hours of study on economics and chemistry is 12. So, if hours of study on economics is $x$, hours of study on chemistry is $12 - x$.

Step2: Analyze grade - changes

When dividing study time equally (6 hours each), grade is C in both. For each additional 3 - hour block for one subject, its grade increases by one letter and the other's grade decreases by one letter.

Hours of Study on Economics	Hours of Study on Chemistry	Expected Grade in Economics	Expected Grade in Chemistry
9	3	B	D
6	6	C	C
3	9	D	B
0	12	F	A

Answer:

Hours of Study on Economics	Hours of Study on Chemistry	Expected Grade in Economics	Expected Grade in Chemistry
9	3	B	D
6	6	C	C
3	9	D	B
0	12	F	A