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3 years ago

A teacher figures out her students’ final grade in the class by finding the mean of the following three

Mathematics

2 answers:

Oduvanchick [21]3 years ago

4 0

Answer:

95%

Step-by-step explanation:

To find the average, we add up all the scores and divide by 3.

We know 2 of the scores, but one is unknown, we will call it x.

$\frac{x+90+70}{3}$

Jenny wants the average to be 85, so we can set the expression equal to 85

$\frac{x+90+70}{3}$ =85

Multiply by 3 on both sides

160+x=255

Subtract 160 from both sides

x=95

She will have to score a 95 to pass the class with an 85 average

Hope this helps!

son4ous [18]3 years ago

4 0

Answer:

She would have to score a 75 or more

Step-by-step explanation:

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