COMBINED VARIATION
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Solve:
[tex] \implies \sf \large a = \frac{kb}{c} \\ [/tex]
[tex]\large \tt \red{given} \begin{cases} \sf \: a = 40 \\ \sf \: b = 4 \\ \sf \: c = 2 \end{cases} \\ \\ [/tex]
[tex] \implies \sf \large 40 = \frac{k(4)}{2} \\[/tex]
[tex] \implies \sf \large 40 = k(2)[/tex]
[tex] \implies \sf \large \frac{40}{2} = \frac{k( \cancel2)}{ \cancel2} \\ [/tex]
[tex] \implies \sf \large \therefore \: {k = 20}[/tex]
[tex] \: [/tex]
[tex]\large \tt \red{given(2)} \begin{cases} \sf \: k = 20 \\ \sf \: b = 15 \\ \sf \: c = 25 \end{cases} \\ \\ [/tex]
[tex] \implies \sf \large a = \frac{20(15)}{25} \\ [/tex]
[tex]\implies \sf \large a = \frac{300}{25} \\ [/tex]
[tex]\implies \sf \large \therefore \: \orange{a = 12 } [/tex]
[tex] \: [/tex]
Final Answer:
[tex] \sf \huge \orange{a = 12}[/tex]
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