Arithmetic rule

Multiplication and Division Significant Figures

For multiplication and division, the input with the fewest significant figures controls the final answer.

Use the fewest significant figures

In 2.50 × 3.1, the raw result is 7.75. Because 3.1 has two significant figures, the final answer is 7.8.

Find the significant figures in each measured value first, then round only the final result. Avoid rounding intermediate values too early.

For 10.0 ÷ 4.0, both inputs are checked by significant figures. The final result uses the fewest count among the inputs.