Decimals

<p><a target="_blank" href="https://www.prepswift.com/quizzes/quiz/prepswift-decimals"><span style="font-size:22px">Decimals Exercise</span></a></p><p><strong><span style="color:#27ae60;">Decimals</span></strong> - more accurately the <strong>Decimal Number System</strong> - was an&nbsp;<strong><u>amazing</u></strong>&nbsp;invention, for several reasons.</p> <ul> <li>It is a positional number system, meaning that the location of a digit in a number influences its value. <ul> <li>For example, in the numbers $30$ and $300$, the $3$ represents different values. In the first, it is $3 \times 10^1$ and in the second it is $3 \times 10^2$</li> <li>Before the invention of positional number systems, you had to keep adding characters to represent larger numbers. For example, this is the number $3$,$888$ in Roman numerals: <ul> <li>MMMDCCCLXXXVIII</li> </ul> </li> </ul> </li> <li>It uses only $10$ characters to express an infinite number of numbers: <ul> <li>$0$, $1$, $2$, $3$, $4$, $5$, $6$, $7$, $8$, $9$</li> </ul> </li> <li>It is a &quot;base-10&quot; number system. This is intuitive to humans, likely because we have ten fingers. <ul> <li>There are other &quot;base&quot; systems, like binary ($2$ characters), hexadecimal ($16$ characters), vigesimal ($20$ characters), and sexagesimal ($60$ characters).</li> <li>It&#39;s true that other &quot;base&quot; systems have fewer characters, but they wouldn&#39;t be as intuitive (remember our $10$ fingers).</li> </ul> </li> <li>It uses the digit $0$ to indicate &quot;there is nothing in this place.&quot; This is an incredibly useful invention. <ul> <li>For example, in the number $405.02$, the $0$s tell us there is nothing in the tens place or tenths place.</li> </ul> </li> </ul>