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the average of your 3 quiz grades is 17 points. two of your quiz grades are 14 points and 19 points.write and solve an equation to find the third quiz grade

User Ted Ballou
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2 Answers

7 votes
14 + 19 + x = 17 x 3
14 + 19 + x = 51
33 + x = 51
x = 18

Check 14+19+18=51 and 51 divided by 3 (quizzes) = 17 (the average in the problem)
User Mookie
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3 votes

there are three quizzes held

average grades of the three quizzes are calculated by taking the sum of the three quiz grades and dividing by 3

average grade is 17 points

1 quiz grade - 14 points

2nd quiz grade - 19 points

3rd quiz grade - x

the equation we can write to find x is


((14 + 19+x))/(3) = 17

next we solve it

14 + 19 + x = 51

33 + x = 51

x = 18

therefore third quiz grade is 18

User Glen Blanchard
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7.9k points