SOLUTION: Aura took three biology exams and has an average score of 85. Her second exam score was 11 points better than her first, and her third exam score was 2 points better than her secon

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Question 570635: Aura took three biology exams and has an average score of 85. Her second exam score was 11 points better than her first, and her third exam score was 2 points better than her second exam. What were her three exam scores?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Let Aura's three biology test scores be: a, b, and c. The average of these is:
%28a%2Bb%2Bc%29%2F3+=+85 So the sum (S) of the three scores is:
S+=+3%2885%29
S+=+255 Now...
b+=+a%2B11 "Her second exam score (b) was 11 points better than her first,..."
c+=+b%2B2 "...and her third exam score (c) was 2 points better than her second exam (score)."
Starting with:
a%2Bb%2Bc+=+255 Substitute b+=+a%2B11 and c+=+b%2B2=a%2B11%2B2+=+a%2B13 so we have:
a%2B%28a%2B11%29%2B%28a%2B13%29+=+255 Simplify.
3a%2B24+=+255 Subtract 24 from both sides.
3a+=+231 Divide by 3.
a+=+77 and b+=+77%2B11=88 and c+=+77%2B13 = 90