SOLUTION: The mean for a set of 28 scores is 80. Suppose two more students take the test and score 60 and 50. What is the new mean?

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Question 315513: The mean for a set of 28 scores is 80. Suppose two more students take the test and score 60 and 50. What is the new mean?
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
The mean for a set of 28 scores is 80. Suppose two more students take the test and score 60 and 50. What is the new mean?

AVERAGE+=+%28SUM_OF_SCORES%29%2F%28NUMBER_OF_STUDENTS%29

When there are 28 students,

80=%28SUM_OF_SCORES%29%2F28

Multiply both sides by 28:

2240 = SUM_OF_SCORES

Now after those two extra students take the test,
the new sum of scores will be 2240 + 60 + 50 = 2350,
and the number of students will be 28 + 2 = 30 

Using the formula again:

AVERAGE+=+%28SUM_OF_SCORES%29%2F%28NUMBER_OF_STUDENTS%29

AVERAGE+=+2350%2F30=78%261%2F3

Edwin