# 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 are taught in your class.

Regardless of what your instructor or textbook teaches, you must follow the rules listed here to receive credit for answers that are required to be specified to a certain number of significant figures. If your instructor or textbook teaches significant figures differently than these rules, tell your instructor. Your instructor can turn off significant figure checking for 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 |