[tex] \frac{n}{5} = \frac{72}{8} \\ \\ \frac{n}{5} = 9 \\ \\ n = 9 \times 5 \\ \\ n = 45 \\ \\ [/tex]
The final result is: n = 45.
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[tex] \frac{9}{n} = \frac{4}{18} \\ \\ \frac{9}{n} = \frac{2}{9} \\ \\ 9 = \frac{2}{9} n \\ \\ 9 = \frac{2n}{9} \\ \\ 9 \times 9 = 2n \\ \\ 81 = 2n \\ \\ \frac{81}{2} = n \\ \\ n = \frac{81}{2} \\ \\ [/tex]
The final result is: n = 81/2 or n = 40.5.
