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Abby's average after taking 31 quizzes is 76. After her teacher drops Abby's 3 lowest test scores, her average increases to 81. What is the average of Abby's three lowest test scores?

User Chathz
by
5.8k points

2 Answers

3 votes

Answer:

29.3

Explanation:

According to the question, Abby's average after taking 31 quizzes is 76. After her teacher drops Abby's 3 lowest test scores, her average increases to 81. What is the average of Abby's three lowest test scores?

Let's assume the total score of the 31 quizzes Abby took as x and the average of those scores is 76

To find out the yotla scores we do a cross multiply and we have

X = 76 × 31

X = 2356

And if her 3 lowest scores were removed and she had an average of 81,her total score was 81 × 28 = 2268

Now to find out the average of the lowest score,we subtract both scores and get their average

2356 - 2268 = 88/3

= 29.3

User Dmitrii Dushkin
by
6.2k points
7 votes

Answer: 29.3

Explanation:

Abby's average after taking 31 quizzes is 76.

Total test scores= 31 × 76 = 2356

After Abby's teacher drops her 3 lowest test scores, her average increases to 81. This means that (31-3)= 28 test scores were used.

Total scores = 28 × 81 = 2268

Sum of Abby's three lowest score

= 2356 - 2268

= 88

Average of the three scores will now be 88 divided by 3

= 88/3

= 29.3

The average is 29.3

User Niko Efimov
by
5.3k points