National 4; Rounding and Estimating Rounding and estimating. A way of approximating or estimating an answer is to round off using significant figures. You can then select and carry out ...

For most filers, rounding off usually makes little difference in their total tax. But the way the IRS sets up its tax tables, not keeping a close eye on the pennies can cost you a few dollars.

We round off a number using a certain number of significant figures. The most common are \(1, 2 \)or \(3\) significant figures. Remember the rules for rounding up are the same as before: ...