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natasha wants to average at least 90% in math class. her test scores so far are 94%, 89%, 88%, 92%, and 85%. what score does she need to earn on her next test to reach her goal? show your work.

User Gonjila
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1 Answer

3 votes

Hey there! Johnny Sins always here to help,

To find out what score Natasha needs to earn on her next test, we can use the following formula:

Average = (sum of all scores) / number of scores

Let's call the score Natasha needs to earn on her next test "x".

Her average so far is:

Average = (94 + 89 + 88 + 92 + 85) / 5 = 90

Her average after her next test will be:

Average = (94 + 89 + 88 + 92 + 85 + x) / 6

Now, we need to set this equal to 90% and solve for x:

90 = (94 + 89 + 88 + 92 + 85 + x) / 6

90 * 6 = (94 + 89 + 88 + 92 + 85 + x)

540 = (94 + 89 + 88 + 92 + 85 + x)

x = 540 - (94 + 89 + 88 + 92 + 85)

x = 540 - 448

x = 92

So, Natasha needs to earn a 92% on her next test to average at least 90%.

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No problem for the answer, be sure o give a 5 stars and thanks,

Johnny Sins

User Maxii
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