192k views
0 votes
On two​ examinations, you have grades of 8787 and 8989. There is an optional final​ examination, which counts as one grade. You decide to take the final in order to get a course grade of​ A, meaning a final average of at least 90. a. What must you get on the final to earn an A in the​ course? b. By taking the​ final, if you do​ poorly, you might risk the B that you have in the course based on the first two exam grades. If your final average is less than​ 80, you will lose your B in the course. Describe the grades on the final that will cause this to happen.

1 Answer

0 votes

Answer:

Step-by-step explanation:

a.

Suppose that "x" is your final exam grade.

Then you want: (87 + 89 + x ) / 3 ≥ 90

(176 + x )/3 ≥ 90

We then multiply the equation by 3 and get

176 + x ≥ 270

Hence x ≥ (270-176)

we get: x ≥ 94

To get A Grade in a course, You must get at least a 94 on the final exam.

b.

If your final average is less than 80, You will lose your B in course

i.e (87 + 89 + x ) / 3 < 80

(176 + x )/3 < 80

We then multiply the equation by 3 and get

176 + x < 240

Hence x < (240-176)

we get: x < 64

You will lose your "B" if your Final grade is less than 64

User MishaU
by
3.0k points