What is 0.209 rounded to 1 significant figure?

Answer 1

The first step in taking any number to 1 significant figure is to find the greatest non-zero digit. In this case it is the 2, as that represents 2 tenths. The next step is to look at the next digit on. If it is 5, 6, 7, 8 or 9 we need to round up. Otherwise, we can leave it as it is. The next digit is 0, so we don't need to round up. Therefore 0.209 rounded to 1 significant figure is 0.2