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A student has successfully passed 60 percent of the 20 quizzes he has written so far. If the student writes 50 quizzes during the year, and successfully passes 80 percent of the remaining quizzes, what is his percent success rate for all his quizzes for the entire year? help

User Michael L
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2 Answers

7 votes

Answer:

74.29%

Explanation:

A student passed 60%, or a proportion of 0.60 of the 20 quizzes he's written so far. This means he has passed
0.60*20=12 quizzes so far.

Now he has written 50 quizzes and passed 80% of them, or
50*.8=40 quizzes.

To find the success rate, take the number of quizzes passed and divide by total number of quizzes.


(Passed)/(Total)=
(12+40)/(20+50)=
(52)/(70)=.7429

To get a percentage, multiply this proportion by 100 to get 74.29%

User HepaKKes
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5 votes
His percent success rate is 72%
User Sparknoob
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5.9k points