# How WebAssign Calculates Significant Figures

Because textbooks and instructors sometimes use different rules for determining significant figures, WebAssign might calculate the "correct" number of significant figures in a different way than you teach in your class.

If you teach significant figures using different rules than are listed here, do not enable significant figure checking in your assignments.

## Rules for Significant Figure Calculations in WebAssign

Operation | Rule | Examples |
---|---|---|

Addition |
Use the fewest number of decimal places specified in any of the operands. |
10 + 1 = 10 |

Subtraction |
Use the fewest number of decimal places specified in any of the operands. |
10 - 1 = 10 |

Multiplication |
Use the fewest number of significant figures specified in any of the operands. |
1530 × 4.0 = 6100 |

Division |
Use the fewest number of significant figures specified in any of the operands. |
444 ÷ 4 = 100 |

Exponentiation |
Use the same number of significant figures as the base. |
2 |

Logarithms |
Use the same number of |
log |

Antilogarithms |
Use the same number of |
10 |