40 lines
627 B
TeX
40 lines
627 B
TeX
\documentclass[a4paper,10pt]{article}
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\usepackage[utf8]{inputenc}
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%opening
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\title{}
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\author{}
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\begin{document}
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\maketitle
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\begin{abstract}
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\end{abstract}
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\section{McDonalds maths puzzle etc.}
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Where $D$ is a drink, $B$ is a burger and $F$ is fries:
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$$ D + D + D = 30 $$
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so $D$ == 10
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$$ D + B + B = 20 $$
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so $B$ == 5
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$$ B + FF + FF = 9 $$
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so $FF + FF = 4$ therefore $FF=2$ so $F=\pm \sqrt{2}$
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Onto the final equation
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$$B + F \times D = \; ? $$
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As $F$ is $\pm \sqrt{2}$
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there are two valid answers
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$ 5 + \sqrt{2} \times 10 $ and $ 5 - \sqrt{2} \times 10 $
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So the answer is either 19.142 or -9.142.
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\end{document}
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