Question

Compute 9.3456+2140.56. Round the answer appropriately. Express your answer numerically using the proper number of significant figures.

Answer 1

When you are adding, you have to count the number of significant figures after the decimal point.

The result must have the same number of significant figures after the decimal point as the original number with less significant figures after the point.

The numbers we have are:

9.3456, this has 4 significant figures after the point.

2140.56, this one has 2 significant figures

The result is 2149.9056

As we said before, the result must have the same significant figures after the point like 2140.56.

Since there is a 5 in .905, we must round it, so the result you should report is:

2149.91