Which of the following measurements is expressed to three significant figures?

0.004 g

0.040 g

4044.0 g

4.40 x 10^-14 g

Question

Which of the following measurements is expressed to three significant figures?
		
0.004 g
		
0.040 g
		
4044.0 g
		
4.40 x 10^-14 g    <--- Correct?

mathmate · Answer

Yes, correct.  4.40 has 3 significant figures, no matter which power of 10 it is mulitplied by.
0.004 has one significant figure (leading zeroes don't count)
0.040 has two, again, leading zeroes don't count.
4044.0 has 5 significant figures, because counting starts from the first non-zero digit (4) and ends with the last non-zero digit, or trailing zero(es) AFTER the decimal point, if there is any.