SOLUTION: professor Abel corrected 20 papers and found the mean to be 70. He then corrected 30 more papers and found the mean for this group to be 80. What is the mean of he combined group
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Question 325922: professor Abel corrected 20 papers and found the mean to be 70. He then corrected 30 more papers and found the mean for this group to be 80. What is the mean of he combined group of 50 students? Answer by AAfter Search(61) (Show Source):
You can put this solution on YOUR website! Total marks of 20 papers is 20 x 70 = 1400
Total marks of 30 papers is 30 x 80 = 2400
Total marks of 50 papers of (1400 + 2400) = 3600
Mean marks of 50 papers is 3600/50 = 72
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