What type of decimal number represents less than a whole number?

The type of decimal number that represents less than a whole number is a decimal fraction. Decimal fractions are used to express values that are between whole numbers, typically in a format that includes a decimal point followed by digits. For example, in the number 0.75, the '0' indicates it is less than one whole unit, and the 75 represents a fractional part of a whole number, specifically three-quarters.

Decimal fractions serve a critical purpose in various fields, including welding print reading, where precise measurements that fall between whole numbers often need to be conveyed. This allows for accurate and effective communication of dimensions, tolerances, and other quantitative factors essential to achieving quality workmanship in welding and fabrication.

The other options are not applicable in this context. A decimal whole would refer to whole numbers expressed in decimal form, which does not include values less than one. A decimal point is simply the symbol used to separate the whole part from the fractional part of a decimal number and does not represent a quantity on its own. Lastly, a decimal ratio compares two quantities and typically does not specifically indicate a value less than one.