Sagot :
PROPORTION
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[tex] \implies \sf \large \frac{ \blue2}{ \green{9}} = \frac{ \green{n}}{ \blue{81}} \\ [/tex]
[tex] \implies \sf \large \green{9n} = \blue{162}[/tex]
[tex] \implies \sf \large \frac{ \cancel9n}{\cancel9} = \frac{162}{9} \\ [/tex]
[tex] \implies \sf \large \therefore \: \orange{n = 18}[/tex]
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[tex] \sf \: \: \large \overbrace { \blue5 \: : \: \overbrace { \green{12 } = \green{35}}^{ \green{means}} \: : \: \blue{n} }^{ \blue{extremes}} [/tex]
[tex] \sf \implies \large \blue{5n} \: = \: \green{420}[/tex]
[tex] \sf \implies \large \frac{ \cancel5n}{ \cancel5} = \frac{420}{5} \\ [/tex]
[tex] \implies \sf \large \therefore \: \orange{n = 84}[/tex]
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[tex] \sf \: \: \large \overbrace { \blue2 \: : \: \overbrace { \green{n } = \green{4}}^{ \green{means}} \: : \: \blue{18} }^{ \blue{extremes}} [/tex]
[tex] \implies \sf \large \green{4n} = \blue{36}[/tex]
[tex]\sf \implies \large \frac{ \cancel4n}{ \cancel4} = \frac{36}{4} \\ [/tex]
[tex]\implies \sf \large \therefore \: \orange{n = 9}[/tex]
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