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Example Questions
Example Question #1 :Decimals
Writein scientific notation.
We want to move the decimal point to the place just after the first non-zero number, in this case 6, and then drop all of the non-significant zeros. We need to move the decimal point five spaces to the right, so our exponent should be negative. If the decimal had moved left, we would have had a positive exponent.
In this case we get 6.009 * 10–5.
Example Question #1 :How To Convert Decimals To Scientific Notation
is equal to which of the following?
We need to convertinto a number of the form.
The trick is, however, figuring out whatshould be. When you have to move your decimal point to theright, you need to make the decimal negative. (Note, though, when you multiply by a negative decimal, you moveto the left. We are thinking in "reverse" because we are converting.)
Therefore, for our value,. So, our value is:
问题# 3:例子How To Convert Decimals To Scientific Notation
is equal to which of the following?
The easiest way to do this is to convert each of your answer choices into scientific notion and compare it to.
为每一个of the answer choices, this would give us:
(Which is, thus, the answer.)
When you convert, youaddfor each place that you move to theleftandsubtractfor each place you move to theright. (Note that this is opposite of what you do when you multiply out the answer. We are thinking in "reverse" because we are converting.)