Marta wants to have at least an average of 90% in her class. Her grade is calculated by averaging her homework score and the scores from five exams. Her homework grade and scores from the first four exams are given below 88%, 86%, 89%, 85%, 99% If all scores are weighted equally, what score does Marta need on her final exam to get a 90% average? Round to the nearest tenth if necessary

Question

Mathematics

Ronin Saunders

1 March, 07:06

Marta wants to have at least an average of 90% in her class. Her grade is calculated by averaging her homework score and the scores from five exams. Her homework grade and scores from the first four exams are given below 88%, 86%, 89%, 85%, 99% If all scores are weighted equally, what score does Marta need on her final exam to get a 90% average? Round to the nearest tenth if necessary

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Answers (1)

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Honey Pie · Answer 1

The weighted average is:

P = ((note) * (weight)) / (weight)

As the weight is the same then we have:

P = (88 + 86 + 89 + 85 + 99 + x) / (6)

To achieve an average of 90% we have:

90 = (88 + 86 + 89 + 85 + 99 + x) / (6)

Clearing x:

x = (90 * 6) - (88 + 86 + 89 + 85 + 99)

x = 93%

Answer:

Marta needs on her final exam 93% to get to 90% average