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Number theory Difficulty 6.4 National olympiad Find the answer

Example 11 Find the least common multiple of 8127,11352,216728127, 11352, 21672 and 27090.

A number or a short expression. Spacing and $ signs are ignored.

Solution

Since
\begin{array}{|c|c|c|} \hline 1 & \begin{array}{l} \begin{array}{l} 8127 \\ 6450 \end{array}
\end{tabular} & \begin{array}{l} \begin{array}{r} 11352 \\ 8127 \end{array}
\end{tabular} \\
\hline 1 & 1677 & 3225 \\
\hline & 1548 & 1677 \\
\hline 12 & 129 & 1548 \\
\hline & & 1548 \\
\hline & 129 & 0 \\
\hline
\end{tabular}

Therefore, (8127,11352)=129(8127,11352)=129, and by Lemma 10 we have
{8127,11352}=8127×11352129=715176 \{8127,11352\}=\frac{8127 \times 11352}{129}=715176

Since
71517621672715176021672 \begin{array}{|r|l|} 715176 & 21672 \\ 715176 & \\ \hline 0 & 21672 \end{array}

Therefore, (715176,21672)=21672(715176,21672)=21672, and by Lemma 10 we have
{715176,21672}=715176×2167221672=715176 \{715176,21672\}=\frac{715176 \times 21672}{21672}=715176

Since
271517627090704340216721083654181083605418 2\left|\begin{array}{r|r|}715176 & 27090 \\ 704340 & 21672 \\ \hline 10836 & 5418 \\ 10836 & \\ \hline 0 & 5418\end{array}\right|

Therefore, (715176,27090)=5418(715176,27090)=5418, and by Lemma 10 we have
{715176,27090}=715176×270905418=3575880 \{715176,27090\}=\frac{715176 \times 27090}{5418}=3575880

Thus, we have
{8127,11352,21672,27090}=3575880. \{8127,11352,21672,27090\}=3575880.

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.