There are 3 significant figures in this number.
2 of them.
4
111.009 mm rounded off to four significant figures is 111.0
The least number of significant figures in any number of the problem determines the number of significant figures in the answer.
2 significant figures.
There are 3 significant figures in this number.
3 significant figures.
It has 2 significant figures. However, the fact that it is given as 2300 mm and not as 230 cm suggests that it is, in fact significant to 4 figures.
2 of them.
4
4. The zeroes to the left are not significant, the zero to the right, is.
111.009 mm rounded off to four significant figures is 111.0
3 of them.
The least number of significant figures in any number of the problem determines the number of significant figures in the answer.
110.1mm
There are six significant figures in the measurement of 45.0300 mm. All non-zero digits and zeros between them are significant, as well as any zero to the right of a decimal point.