Help with math problem.

[Pandora333 48]

Perhaps this isn't the best place to ask for help, specially with math, but I have to try at least. http://kh13.com/forum/public/style_emoticons/default/happy.png

 

Here's the problem.

 

In a exam, the highest grade was 100 with 34 correct answers and the lowest was 50 with 11 correct answers. If I got 85, how many correct answers did I get?

 

Edit: I should have been more specific, I more or less know the answer, but I need to know how to do it.

Edited March 25, 2012 by Pandora333

[darkchaser 788]

ima have to say 28 or 29

[Kirie 3,489]

Hmm.....

[Junko 2,815]

i got like 28.9 so u may have to round it to 29

[Pandora333 48]

i got like 28.9 so u may have to round it to 29

 

But how did you do it?

[darkchaser 788]

But how did you do it?

 

34/100=x/85 cross multiply to get 100x=34(85) then divide by 100 to get x=28.9

[Loki 1,184]

Your phrasing is a bit confusing. So there were 34 questions, but if you got 11 correct (which would be 32%) you would still get a 50%? Some grading curve. Were all the questions the same amount of points? I would go with 29 correct, but if your teacher is using some firetrucked up grading scale, then who knows. Edited March 25, 2012 by Loki

[Pandora333 48]

34/100=x/85 cross multiply to get 100x=34(85) then divide by 100 to get x=28.9

 

But if I use 11 instead of 34, the answer is different. Here's my logic

 

11/50=x/85 ----> 50x=(11)(85) = 18.7

 

Your phrasing is a bit confusing. So there were 34 questions, but if you got 11 correct (which would be 32%) you would still get a 50%? Some grading curve. Were all the questions the same amount of points? I would go with 29 correct, but if your teacher is using some firetrucked up grading scale, then who knows.

 

It's a math problem. And yes, all the answers have the same value. I wasn't there when my teacher explained this. According to some of my classmates the right thing to do is to obtain the value of each answer. This by substracting the lowest grade to the highest. Then, do the same with the answers.

 

Something like this:

 

100-50=50 ---- 34-11=25

 

But I don't know what I have to do next. If to do 25/50 or 50/25.

 

So confusing.

 

This problem is an example from a national evaluation called ENLACE here in Mexico. There goes why we're so bad in education.

Edited March 25, 2012 by Pandora333

[darkchaser 788]

But if I use 11 instead of 34, the answer is different. Here's my logic

 

11/50=x/85 ----> 50x=(11)(85) = 18.7

 

true but 29 is a more reasonable answer cuz 85 is closer to 100 and 29 is closer to 34

[Junko 2,815]

But how did you do it?

 

i basically did what darkchaser did and yeah, 29 sounds like the better answer

[AnsemTheWise 1,114]

If there were 34 questions, and you got an 85 on the test, just find 85% of 34.

 

34 x 0.85= 28.9

 

29-ish questions correct.

[Vanitas 127]

I got 28.9

 

But you cant have 9/10 of a problem correct Unless partial credit

 

I'd say 28

 

I did 85over a 100 times x over 34.

 

34 times 85 equals 2890.

2890 divided by a 100 equals 28.9.

 

 

I rounded down. ^ Look up

 

 

 

11/50=x/85 ----> 50x=(11)(85) = 18.7

^ I believe problem here is that the test is out of a hundred. Since in this case 11/50 is not out of a hundred it wont work. 11/50 equals 22/100. 22 = questions correct. 34 total questions. 11/50 does not work. Has to be out of a hundred