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3 years ago

Micheal's mean score for five tests was 82. if four of those tests were 83,75,93, and 67, what was the fifth score on his test?

Mathematics

1 answer:

bezimeni [28]3 years ago

5 0

Let T represent the fifth test score. The average is the sum of scores divided by their number.

... 82 = (83 +75 +93 +67 +T)/5

... 410 = 318 +T . . . . . . . multiply by 5

... 92 = T . . . . . . . . . . . . subtract 318

The fifth score was 92.

_____

One of the ways I like to work problems like these is to add the differences from the mean. Those are ...

1, -7, 11, -15

so their sum is -10.

The final score must be 10 above the mean in order for this total to be zero. 10 above the mean is 92.

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Step-by-step explanation:

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3 years ago

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Question is Incomplete, Complete question is given below.

Prove that a triangle with the sides (a − 1) cm, 2√a cm and (a + 1) cm is a right angled triangle.

Answer:

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Step-by-step explanation:

Given : Triangle having sides (a - 1) cm, 2√a and (a + 1) cm.

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