Question 577913
A teacher has two math classes. 
In one class there are 80 students and the average grade on a test was 30. 
Total points = 80*30 = 2400
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In her other class there are 40 students and the average grade on the same test is 50.
Total points = 40*50 = 2000
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What is the average grade of all her students?
Aver = total points/total # of students 
= (2400+2000)/(80+40) 
= 4400/120 
= 36 2/3
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Cheers,
Stan H.
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