Suppose y varies inversely as x and y =24 when x= 3. Find x when y = 36.

So I worked it out I got this:

36 -24 = x - 3

12+3 = 15

15 =x

y=36 , x=15

Is this right?

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- July 3rd 2005, 01:01 PMHayabusaHelp check please
Suppose y varies inversely as x and y =24 when x= 3. Find x when y = 36.

So I worked it out I got this:

36 -24 = x - 3

12+3 = 15

15 =x

y=36 , x=15

Is this right? - July 3rd 2005, 01:34 PMticbol
"y varies inversely as x "

y ----> 1/x

y = k(1/x) ----the equation.

y=24 when x=3, so,

24 = k(1/3)

24 = k/3

24*3 = k

k = 72

Hence, when y = 36,

36 = 72(1/x)

36 = 72/x

36x = 72

x = 72/36 = 2 ---answer.

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Another meaning of "y varies inversely as x" is:

if x goes higher, then y goes lower; if x goes lower, then y goes higher...proportionately. - July 3rd 2005, 03:22 PMHayabusa
thank you :)