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xeze [42]
3 years ago
6

A student receives 83.2 points, 44.6 points, 74.4 points, and 52.3 points on each of four tests. Determine the student's test av

erage with the correct significant digits.
Chemistry
1 answer:
kow [346]3 years ago
3 0

Answer:

The average is 63.6

Explanation:

<u>Step 1: Calculate the total points of all tests together</u>

The total of the 4 tests is : 83.2 points + 44.6 points + 74.4 points + 52.3 points = 254.5 points

<u>Step 2: Calculate the average points</u>

We have 4 tests so we divide the total number by 4

254.5 points  / 4 = 63,625 points

<u>Step 3: take significant digits into account</u>

<em><u>Sum or difference :</u></em><u> </u>Add or subtract in the normal way, then round the answer to the LEAST number of places to the decimal point of any number in the problem

⇒ in this case : 83.2 + 44.6 + 74.4 + 52.3 = 254.5

<u>Multiplication and division:</u> the answer is reported in such a way that it reflects the reliability of the least precise operation. Your answer cannot be MORE precise than the least precise measurement.

254.5 / 4 = 63.6

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