Question

Y varies inversely as x, and y = 50 when x = 10. What is the value of y when x = 20? 100

25
10

Answer 1

`y=25`

Explanation:

We have been given that y varies inversely as x and
`y=50`, when
`x=10`.

We know that when y varies inversely with x, then the equation is:
`y=(k)/(x)`, where, k represents constant of variation.

First of all, we will find constant of variation using point
`y=50`, and
`x=10` as shown below:

`50=(k)/(10)`

`50*10=(k)/(10)*10`

`500=k`

Upon substituting
`k=500` in inversely proportion we will get:

`y=(500)/(x)`

To find the value of y, we will substitute
`x=20` in above equation as:

`y=(500)/(20)`

`y=(50)/(2)`

`y=25`

Therefore, the value of y is 25.