All measurements have some degree of uncertainty due to human error and the sophistication of the measuring device. This is expressed in the measurement in terms of the number of significant figures. 0.1, where the error is estimated based on the decimal place of the last digit. 0.1 mL, and the true value lies between 9.9 and 10.1 mL. A graduated cylinder is more accurate than a beaker or a volumetric flask. Accuracy refers to how closely a measurement value agrees with the correct value.
Precision refers to how closely individual measurements agree with each other.
The result of a calculation based on experimental measurements cannot be more precise than the measurement that has the greatest uncertainty. A measurement can only be reported to the extent or degree of certainty, or uncertainty, for that matter. The quality of a measurement depends on the quality of the measuring device or instrument . Some simple rules govern the use of significant figures in calculations. Zeroes used to position the decimal point are not significant figures.