If x - y and x-20 when y-5- find the constant of variation k-

Given proportion is x∝ y ⇒ x=ky #160;(where k is a constant of variation) ⇒ k= x y #160; #160; #160;....(1)Substituting ...

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Standard VI

Mathematics

Proportions

If x ∝ y an...

Question

If $x \propto y$ and $x = 20$ when $y = 5$ , find the constant of variation $(k)$ .

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Solution

Given proportion is $x \propto y$
$\Rightarrow x = k y$ (where $k$ is a constant of variation)
$\Rightarrow k = \frac{x}{y}$ ....(1)
Substituting $x = 20$ and $y = 5$ in equation (1), we get
$k = \frac{20}{5} = 4$
$∴$ constant of variation $(k) = 4$ .

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If x∝y and x=20 when y=5, find the constant of variation (k).

Given proportion is x∝y⇒x=ky (where k is a constant of variation)⇒k=xy ....(1)Substituting x=20 and y=5 in equation (1), we getk=205=4∴ constant of variation (k)=4.

If $x \propto y$ and $x = 20$ when $y = 5$ , find the constant of variation $(k)$ .

Given proportion is $x \propto y$
$\Rightarrow x = k y$ (where $k$ is a constant of variation)
$\Rightarrow k = \frac{x}{y}$ ....(1)
Substituting $x = 20$ and $y = 5$ in equation (1), we get
$k = \frac{20}{5} = 4$
$∴$ constant of variation $(k) = 4$ .