y and x have the relation of inverse variation between them y = 10, when x = 15
Find y when x = 20.

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Solution

$y α \frac{1}{x} ∴ y \times x = k (k is a constant .) \Rightarrow 10 \times 15 = k (y = 10 w h e n x = 15 .) \Rightarrow k = 150 x y = 150 (Equation of variation) When 20 y = 150, (∵ x = 20) y = \frac{15}{2} = 7.5$

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y and x have the relation of inverse variation between them y = 10, when x = 15 Find y when x = 20.

y α 1x∴ y×x=k (k is a constant.)⇒ 10×15=k (y=10 when x=15.)⇒ k=150xy=150 (Equation of variation) When 20y=150, (∵ x=20)y=152=7.5

y and x have the relation of inverse variation between them y = 10, when x = 15
Find y when x = 20.

$y α \frac{1}{x} ∴ y \times x = k (k is a constant .) \Rightarrow 10 \times 15 = k (y = 10 w h e n x = 15 .) \Rightarrow k = 150 x y = 150 (Equation of variation) When 20 y = 150, (∵ x = 20) y = \frac{15}{2} = 7.5$