30.900 has 5 significant figures.
In 30900 there are [at least] three significant figures.
There are three.
3.
There is one significant digit in the number 10, as written.
30.900 has 5 significant figures.
In 30900 there are [at least] three significant figures.
There are three.
3.
There is one significant digit in the number 10, as written.
One of them.
The sum of numbers can have as many significant figures as the number with the least significant figures in the original numbers. For example, if you add numbers with 3, 4, and 5 significant figures, the sum will have 3 significant figures.
The number 02 has one significant figure because a leading zero is not significant. So the significant figure is the digit 2.
Three significant figures. The two zeroes after the digit 5 are irrelevant.
Five. Count from the first nonzero digit to the last nonzero digit.
5. Count the number of digits from the first non-zero digit to the last non-zero digit.
Two. Although there is no way to be sure that the number is not accurate to the unit's digit.