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Need Help With Decimals

How do you know how where to put the decimal point after working out the answer? I heard it's something like count up the zeroes or something??
Original post by Mia 15
How do you know how where to put the decimal point after working out the answer? I heard it's something like count up the zeroes or something??


Its got to do with rounding the numbers and significant figures. It should be borne in mind that the first sf is not the first digit which is a zero. However, the second, third,fourth, are sf. When they follow after the 1st they are permitted to be a zero.

In simpler terms, find the last digit of the number hypothetically if you are rounding to 3sf then the 3rd sf is the last digit. Then use the digit to the right of the decider exactly like the decimal point. Once that has been completed, fill it up with zeros up to but not beyond the decimel point.

Hope I helped. :smile:

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