If x is inversely proportional to y and x = 40 when y = 5, find (i) the value of x when y = 25, (ii) an equation connecting x and y, (iii) the value of y when x = 400.

Question

asked Apr 16, 2024 126k views

1 Answer

Skeeve · Answer 1 · 2024-04-21T14:16:24+0000

Given : x is inversely proportional to y and x = 40 when y = 5

To Find : (i) the value of x when y = 25,

(ii) an equation connecting x and y,

(iii) the value of y when x = 400.

Solution:

x is inversely proportional to y

$\implies x \ \infty \ 1/y$

$\implies x = k/y$

$\implies xy = k$

x = 40 when y = 5

$\implies 40(5) = k$

$\implies 200 = k$

$\implies xy = 200$

y = 25

$\implies x(25) = 200$

$\implies \bold{x = 8}$

equation connecting x and y

$\bold{xy = 200}$

x = 400 .

$\implies 400(y) = 200$

$\implies \bold{y = 0.5}$