How many significant figures are in the number 0.01080?

Answer 1

Let's take a quick review of sig fig rules:

1. non-zero digits are always significant
2. any zero between non-zero digits is significant
3. trailing zeroes (rightmost zeroes) are significant only when there is a decimal
4. leading zeroes (leftmost zeroes) are NOT significant

Now lets take a look at 0.01080 using the rules above

1. The first two zeroes are leading zeroes --> NOT significant
2. 1 is a non-zero digit --> significant
3. There is a zero between two non-zero digits --> significant
4. 8 is a non-zero digit --> significant
5. the final zero is a trailing zero and there is a decimal present --> significant

Thus, there are four significant figures in the number 0.01080 (1, 0, 8, 0).

Answer 2