SOLUTION: Deon's average mark for his first two spelling tests is 10.After the third test,his average mark for the three tests is 9 .what is his mark on the third test?
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-> SOLUTION: Deon's average mark for his first two spelling tests is 10.After the third test,his average mark for the three tests is 9 .what is his mark on the third test?
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Question 971986: Deon's average mark for his first two spelling tests is 10.After the third test,his average mark for the three tests is 9 .what is his mark on the third test? Answer by rothauserc(4718) (Show Source):
You can put this solution on YOUR website! total for the three test is 9*3 = 27
total for the first two tests is 10*2 = 20, therefore
score on third test is 27 - 20 = 7
