I have a question about significant figures, this question required the value of 109.894 to be rounded to 3 significant figures, so how is 110 correct? I thought trailing zeros in non-decimal numbers are not significant? If this is the case... how would we round this number to 3 sigfig?
The guidelines for significant figures is as follows:
- All digits greater than zero are significant
- All zero's between significant digits are significant
- All zero's before non-zero digits are not significant
Regarding zero's after the decimal place
- If they fall
before a decimal place, they
are not significant
- if they fall
after a decimal place, they
are significant.
For the number 109.894, as the first digit, 1, is greater than zero, this is the first significant figure, and there are significant decimal numbers, the three numbers before the decimal place would be significant. As the following number, 8 is greater than 4, we round up the last digit from 9 to 10. Even though normally 110 would be 2 significant figures as the last value, zero, is before the decimal place, if we take in normal rounding laws, this is the only way that this can correctly be founded to 3 sig fig
Just as an idea, if 109.894 was asked to be rounded to different sig fig values...
1 sig fig:100
2 sig fig: 110
3 sig fig: 110
4 sig fig: 109.9
5 sig fig: 109.89
6 sig fig: 109.894
Sorry...reading that back to myself seemed a little confusing. Give me a yell if it makes no sense