SOLUTION: 2 pupils both score 6 out of 10 for a maths test. What would a 3rd pupil have to score to increase their average score by 1 mark? is the answer 9/10 ? (12/20 + x = 21/30 the

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Question 725559: 2 pupils both score 6 out of 10 for a maths test. What would a 3rd pupil have to score to increase their average score by 1 mark?
is the answer 9/10 ?
(12/20 + x = 21/30 therefore x = 9/10) ?
Answer by fcabanski(1391) About Me  (Show Source):
You can put this solution on YOUR website!
9/10 is correct.


You can also set it up as (6+6+x)/3 = 7 (since you know the new average has to be 7 and sum/# = avg).


12+x = 21 ---> x = 9