Find the fourth proportional to 2xy, x2 and y2.

Find the fourth proportional to 2xy, x² and y².

Sum

Let the fourth proportional to 2xy, x² and y² be n.

`=> 2xy : x^2 = y^2 : n`

`=> 2xy xx n = x^2 xx y^2`

`=> n = (x^2y^2)/(2xy) = (xy)/2`

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Chapter 7: Ratio and Proportion (Including Properties and Uses) - Exercise 7 (D) [Page 102]

Chapter 7 Ratio and Proportion (Including Properties and Uses)
Exercise 7 (D) | Q 9.(i) | Page 102

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