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Kiana wants to have an average of at least 90 on her quizzes. If she took three quizzes and earned an 84, 90 and 97. write out the inequality that would help Kiana find the grade that she needs to make on her 4th quiz.PLESE HELP

User RobClucas
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Her grades in the first three quizzes are 84, 90, and 97.

We will call the grade of the 4th quiz "x".

To find the average of the four quizzes, we need to add all of the scores and divide them by the number of quizzes. In this case, we need to add 84, 90, 97, and x, and divide by 4:


(84+90+97+x)/(4)

And since she wants to have an average of at least 90, the last expression has to be greater or equal to 90, we express this with the symbol ≥.

The inequality that can help her find the grade that she needs is:


(84+90+97+x)/(4)\ge90

From there, she can find the value "x" that she needs for the fourth quiz.

Answer:


(84+90+97+x)/(4)\ge90

User Sharas
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