How do you do test average problems?!!!?

Question

Okay, I'm on my school's academic team, and last week we had a competition. We had many problems akin to: So-in-so has a test average of whatever with test grades of whatever, whatever, whatever, whatever, and whatever. What grade does So-in-so need to make on their next test to get their test average up to whatever? I DIDN'T KNOW HOW TO DO THEM!!! Can anyone explain how to do these to me?

Answer 1

Way to be I was on my school academic team too, I'll help ya out that problem isn't too hard. But I know sometimes those questions are impossible to answer in the 15 seconds or whatever the time limit is.

Take all the scores and add x so like:

88 + 98 + 96 + x

And since you have 4 exams each with 100 points there is a total of 400 points possible.

and if you need to have like a 98% in the class you do the problem like this:

[(88 + 98 + 96 + x)/ 400] * 100 = 98

(88 + 98 + 96 + x)/ 400 = .98

88 + 98 + 96 + x = 392

x = 110 %

so it would be impossible to get a 98% in the class unless there is some extra you could do. But hopely this example helps you understand how to perform the problem. Good luck to you and the team.

Answer 2

The definition of an average (or mean) refers to the quotient you get when you divide the sum of all the data numbers by the number of data numbers you summed.

The average of 20, 30, 40, 60 is (20+30+40+60)/4 = 37.5

Does that help?

Answer 3

okay, so lets say that someone got a 40, a 50 and a 90 they have to have a 60 to pass. 40+50+90+xdivided by 4=average grade!!!
from then, you guess and check and if you do that enough, you find that40+50+90+60divided by 4=60, so you she has to get a test score greater then 60

Answer 4

yes - you write the expression for the average before and after the next test. solving the equation to achieve the whatever level will give you the needed test score.

Answer 5

I kind of doubt your back story, but anyway here goes.

The average is the sum of all scores, divided by the number of scores. So you want the sum of the scores to add up to the number of scores x the target score. Add up the scores you got so far, subtract from number of scores x target score, and you get what you need to make on the next test.

Assuming that your back story is true, the way you'd do this quickly is like this:
When they tell you how many tests there are and the target score, multpily these numbers immediately. Call this number P, for product.
When they tell you the scores so far, add these up. Call this number S, for sum.
Subtract S from P, and there you go.
Hopefully there's someone on your team who can do this kind of mental arithmetic quickly.

.

Answer 6

First, you add together all of the test grades. Next, you divide by the number of grades that you have. That is how you average grade.

Answer 7

Your no longer going to get precisely 86% in your traditional, however you'll get beautiful near. If you had been to get among a ninety seven and one hundred in your scan the following day you're going to be at approximately an 86% traditional although. Why shoot for an detailed 86%? Shoot as top as you'll, guy!

Answer 8

yes