SOLUTION: After a test, a teacher worked out the average mark for her class of 10 pupils. It was 81% One of the pupils scored only 27%, which was much less than any of the other marks.

Question 93779: After a test, a teacher worked out the average mark for her class of 10 pupils. It was 81%
One of the pupils scored only 27%, which was much less than any of the other marks.
The teacher decided to work out a new average, leaving out the lowest mark. What was the new average?
Found 2 solutions by Nate, jim_thompson5910:
Answer by Nate(3500) (Show Source): You can put this solution on YOUR website!
(scores + 27%)/10 = 81%
scores + 27 = 810
scores = 783
~~~
783 / 9 = 87%
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Let x=sum of the scores of the remaining students

First write the percentages in decimal form by dividing by 100:
81 percent=
27 percent=

Set up the equation which represents the average (note: the average can be found by adding up everyone's scores and dividing that sum by the number of students who took the test)

Multiply both sides by 10

Subtract 0.27 from both sides

So the sum of the scores for the remaining 9 students is 7.83. Now divide this sum by 9 to find the new average

Now multiply 0.87 by 100 to get a percentage

So the new average is 87%
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