Addition and Subtraction of Approximate Numbers

In the addition or subtraction of approximate numbers, the entry with the lowest level of accuracy determines the format of the solution.



When adding approximate numbers, it is important to be sure that the accuracy of readings is consistent throughout.


To add a quantity accurate only to the tenths place to a number accurate to the thousandths place will result in a total having accuracy only to the tenths place.

One cannot expect the reading with the higher level of accuracy to improve the reading with only tenths-place accuracy.