92 lines
1.5 KiB
TeX
92 lines
1.5 KiB
TeX
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\section{Division}
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Now that you can multiply, division should be easy. All you need to do is work backwards. \\
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Let's look at our first example again: $3 \times 2 = 6$.
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\medskip
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We can easily see that $6 \div 3 = 2$
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\begin{center}
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\begin{tikzpicture}[scale=1]
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\cdscale{\cdscalefn(2)}{1}{C}
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\cdscale{0}{0}{D}
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\slideruleind
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{\cdscalefn(6)}
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{1}
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{Align here}
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\slideruleind
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{\cdscalefn(2)}
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{1}
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{2}
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\end{tikzpicture}
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\end{center}
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and that $6 \div 2 = 3$:
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\begin{center}
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\begin{tikzpicture}[scale=1]
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\cdscale{\cdscalefn(3)}{-3}{C}
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\cdscale{0}{-4}{D}
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\slideruleind
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{\cdscalefn(6)}
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{-3}
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{Align here}
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\slideruleind
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{\cdscalefn(3)}
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{-3}
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{3}
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\end{tikzpicture}
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\end{center}
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If your left-hand index is off the scale, read the right-hand one. \\
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Consider $42.25 \div 6.5 = 6.5$:
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\begin{center}
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\begin{tikzpicture}[scale=1]
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\cdscale{\cdscalefn(6.5) - \cdscalefn(10)}{1}{C}
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\cdscale{0}{0}{D}
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\slideruleind
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{\cdscalefn(4.225)}
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{1}
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{Align here}
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\slideruleind
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{\cdscalefn(6.5)}
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{1}
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{6.5}
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\end{tikzpicture}
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\end{center}
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Place your decimal points carefully.
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\vfill
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\pagebreak
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\problem{}
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Compute the following using your slide rule. \\
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\begin{enumerate}
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\item $135 \div 15$
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\item $68.2 \div 0.575$
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\item $(118 \times 0.51) \div 6.6$
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\end{enumerate}
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\begin{solution}
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\begin{enumerate}
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\item $135 \div 15 = 9$
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\item $68.2 \div 0.575 = 118.609$
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\item $(118 \times 0.51) \div 6.6 = 9.118$
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\end{enumerate}
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\end{solution}
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\vfill
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\pagebreak
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