SOLUTION: this one has me stumped. I don't know why, I usually can get averages, but my mind is stuck here: 8. The final grade for a particular course is calculated by dividing total poin

Algebra.Com
Question 183117: this one has me stumped. I don't know why, I usually can get averages, but my mind is stuck here:
8. The final grade for a particular course is calculated by dividing total points earned by total points available. There are 120 points available in the first half of the course, and 140 points in the second half of the course. If a student earns 81% in the first half of the course, how many points must the student earn in the second half in order to earn an 80% B final grade?
thanks for the help.
Answer by Edwin McCravy(20055)   (Show Source): You can put this solution on YOUR website!
this one has me stumped. I don't know why, I usually can get averages, but my mind is stuck here:
8. The final grade for a particular course is calculated by dividing total points earned by total points available. There are 120 points available in the first half of the course, and 140 points in the second half of the course. If a student earns 81% in the first half of the course, how many points must the student earn in the second half in order to earn an 80% B final grade? 



81% or .81 of the 120 points available in the first half 
of the course is 97.2 points.

Let x = the number of points to make in the second half

Then total points made in both halves will be 97.2 + x

The total points available in both halves of the course is 120 + 140 = 260



We substitute .8 (the decimal equivalent of 80% for the Average



Can you solve that equation for x?  If not post again.

Answer: 110.8

Edwin
RELATED QUESTIONS

Hi again. I'm sorry to bother you guys again but I have one more question. Here it is: (answered by mananth)
Dear pre-algebra helper/tutor people, For my homework, I am stuck on one problem.... (answered by funmath)
I was working on my homework and this one stumped me. I know there can not be a radical... (answered by timvanswearingen)
So I took 3 tests which I needed a 78% average on. The first 2 were worth 75 each and the (answered by Boreal)
I've been stuck on this problem for a really long time. I'm trying to figure out a... (answered by jim_thompson5910,ewatrrr)
Hi. I'm very confused In how to get the answer to this problem: t-3+2(t+2) I tried to... (answered by ankor@dixie-net.com)
you join an aerobics class at a local gym. the cost is $3 per class plus $10 for the... (answered by monika_p)
I think my problem with these kinds of questions is that I’m having a hard time... (answered by jsmallt9)
I am halfway through this problem and have been working on it/been stuck on it for quite... (answered by josgarithmetic,MathTherapy)