# Numerical Questions

Type a number and optionally a unit. If required, your answer might need to be specified using the correct number of significant figures or decimal places. Note Many textbook questions do not specify significant figures or decimal places in the answer key.

If enabled by your instructor, an answer format tip is displayed below the answer box when it is selected and provides information about the form of the answer that is expected. The answer format tip indicates that a number is expected and might also specify whether significant figures or units will be checked.

If your instructor has enabled it, the sigfig icon is displayed beside the answer box for questions that check for significant figures.

Not all questions accept all kinds of notation. The kind of answer that is expected should be clear from the question.

Notation Examples
A decimal number 35

-2.8

1,000,000.89

A fraction or ratio 3/7
Scientific (e) notation -3.045e2
A number and unit 76.5 cm

20 m/s

An exponent (for example, 4.32) 4.3**2
A simple arithmetic expression 5+(6/7)

Decimal notation follows U.S. convention, with the period (.) as decimal point and commas (,) optionally used to separate of groups of three digits left of the decimal point.

Restriction Commas are not allowed when significant figures are checked.

When entering scientific notation, always use a lowercase e and an integer exponent, for example, 1.23e-5.

Equivalent units can be specified. For example, 1 mi, 5280 feet, and 1760 yards are considered to be the same.

By default, numerical questions require the answer to be within 2% of the correct value. Particular questions, classes, or instructors might require greater accuracy, and will usually inform you if that is the case.