SOLUTION: In a class of 10 people, the average mark for the test was 75%.If an additional person takes the test, what mark must they attain to move the average up 80% - Show calculation pls
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Question 883967: In a class of 10 people, the average mark for the test was 75%.If an additional person takes the test, what mark must they attain to move the average up 80% - Show calculation pls Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! In a class of 10 people, the average mark for the test was 75%.If an additional person takes the test, what mark must they attain to move the average up 80%
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so far, 10 people taking the test scored a total of 10*75=750 points.
let x=score one additional person must make to move the average up to 80
(750+x)/(10+1)=80
750+x/11=80
750+x=880
x=130
score one additional person must make to move the average up to 80=130
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