# Scientific numerical dating

Many other factors enter into the decision whether to write numbers out or to express them in numerals. A zero is written before the decimal point of numbers smaller than 1, while in whole numbers the decimal point should either be dropped or be followed by a zero: -Z234.1-89) of the Canadian Standards Association specifies that groups of three numerals (triads) shall be separated by a space, except in the case of monetary values.

This chapter discusses the most important of these and presents some of the conventions governing the use of special signs and symbols with numerals. It advises against the use of commas as separators.

Except in certain adjectival expressions (see 5.05 Adjectival expressions and juxtaposed numbers) and in technical writing, write out one-digit numbers and use numerals for the rest. Thus, to avoid using numerals at the start of a sentence, rewrite /metric units, decimals are preferred to fractions.

Ordinals should be treated in the same way as cardinal numbers, . Normally, no number should begin or end with a decimal point.

Radiometric dating--the process of determining the age of rocks from the decay of their radioactive elements--has been in widespread use for over half a century.

There are over forty such techniques, each using a different radioactive element or a different way of measuring them.

The rules stated should, in most cases, be regarded as guidelines for general use that may be superseded by the requirements of particular applications. Although both commas and spaces are still widely used in Canada, recommends that, except in financial documents, a space be used instead of a comma.

Such a space is also to be inserted after groups of three digits to the right of a decimal point.

Many are also unaware that Bible-believing Christians are among those actively involved in radiometric dating.

In mathematics, the notion of number has been extended over the centuries to include 0 Calculations with numbers are done with arithmetical operations, the most familiar being addition, subtraction, multiplication, division, and exponentiation. The same term may also refer to number theory, the study of the properties of numbers.

Besides their practical uses, numbers have cultural significance throughout the world.

He was employed at Caltech's Division of Geological & Planetary Sciences at the time of writing the first edition.

He is presently employed in the Space & Atmospheric Sciences Group at the Los Alamos National Laboratory.