VARIATION K2

 

x is inversely proportional to y. x=54 while y=7. Find y when x is 9.

 

Solution

 

x ⍺ k

      y

 

x = k

      y

 

54 = k

        7

 

k = 54 x 7

 

k = 378

 

,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

 

k = 378, y= ?, x = 9.

 

x = k

      y

 

9  = 378

        y

 

y x 9 = 378  x  y   (multiply by y on both sides)

             y

 

9y= 378

 

9y =378           [Dividing by 10 both sides]

9      9

 

Hence y = 42.

 

 

TRY THIS…………….

 

 

x is inversely proportional to y. x=80 while y=4. Find y when x is 10.