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So far in math class, a student's quiz scores are 86%, 82%, 72%, and 69%. What score does the student need on the fifth quiz to have a mean quiz score of 79%? All the quizzes have equal weights. a 86% b 77.25% c 79% d 87%

User Lexi
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1 Answer

3 votes

Answer:

a

Explanation:

the mean =
(total score)/(count)

let the fifth score be x and count = 5, hence


(86+82+72+69+x)/(5) = 79 ( multiply both sides by 5 )

309 + x = 395 ( subtract 309 from both sides )

x = 86

the student requires a score of 86% → a



User Michael Petrov
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8.9k points