Mean proportion of 8 and 18 is………. A) 10B) 16 C) 12D) 9

1.	Mean proportion of 8 and 18 is………. A) 10B) 16 C) 12D) 9
Answer» Correct option is (C) 12 Let mean proportion of 8 and 18 is x. \(\therefore\) 8 : x : : x : 18 \(\Rightarrow\) \(\frac8x=\frac x{18}\) \(\Rightarrow\) \(x^2=8\times18\) \(=2^2\times2\times2\times3^2\) \(=2^2\times2^2\times3^2\) \(=(2\times2\times3)^2\) \(\Rightarrow\) \(x^2=12^2\) \(\Rightarrow\) x = 12 \(\therefore\) Mean proportion of 8 and 18 is 12. Correct option is C) 12

Answer»

Correct option is (C) 12

Let mean proportion of 8 and 18 is x.

\(\therefore\) 8 : x : : x : 18

\(\Rightarrow\) \(\frac8x=\frac x{18}\)

\(\Rightarrow\) \(x^2=8\times18\) \(=2^2\times2\times2\times3^2\) \(=2^2\times2^2\times3^2\) \(=(2\times2\times3)^2\)

\(\Rightarrow\) \(x^2=12^2\)

\(\Rightarrow\) x = 12

\(\therefore\) Mean proportion of 8 and 18 is 12.

Correct option is C) 12

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