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A student has gotten the following grades on his tests. What is the minimum grade he must get on the last test in order to have an average of 82​? 85​, 90​, 79​, 72

2 Answers

3 votes

Answer:

84

Explanation:

Because average is basically the mean, so i used a mean calculator and put in the four grades (numbers) and got an average of 81.5, so then i kept putting an additional other number in and wasn't getting 82, until i put in 84 and all of those numbers together gave me an average of 82.

User KristofferR
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6.0k points
4 votes

Answer:

84

Explanation:

The average is found by adding all the scores together and dividing by the number of scores

Let the unknown score be x

(85+90+79+72+x) /5 = 82

Multiply each side by 5

(85+90+79+72+x) /5*5 = 82*5

(85+90+79+72+x) = 410

Combine like terms

326+x = 410

Subtract 326 from each side

326+x-326 = 410 -326

x =84

User Victor Petit
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5.9k points