SOLUTION: Two classes took a test. Class A averaged 80 and class B averaged 90. The two classes together averaged about 83. Which class has more students?

Question 357818: Two classes took a test. Class A averaged 80 and class B averaged 90. The two
classes together averaged about 83. Which class has more students?
Answer by robertb(5830) (Show Source): You can put this solution on YOUR website!
Let a = # students in class A, b = # students in class B.
Sum of all scores in Class A = 80a,
Sum of all scores in Class B = 90b.
By the given, ,
so , or
,
.
Since a number between 0 and 1 has to be multiplied to a to equal b, then a>b.
Therefore class A has more students.

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