Significant figures are always used when a measurement is made and they express the degree of uncertainty in both measurements
and calculations. In any measurement, the number of significant figures always includes one more decimal place than that obtained
from the smallest calibration on the measuring instrument. All the digits in a measured number are called
significant figures with all but the right-most digit known for sure. The right-most digit has been estimated.
Several rules can be used to determine the number of significant figures when the measurement contains at least one zero. However, a very simple technique called DOT RIGHT, GO RIGHT is much easier to remember.