VARIATIONS D1

 

x is inversely proportional to y. x=22 while y=5. Find y when x is 10.

 

Solution

 

x ⍺ k

      y

 

x = k

      y

 

22 = k

        5

 

k = 22 x 5

 

k = 110

 

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

 

k = 110, y= ?, x = 10.

 

x = k

      y

 

10  = 110

          y

 

y x 10 = 110  x  y   (multiply by y on both sides)

               y

 

 

10y = 110

10      10

 

Hence y = 11.

 

TRY THIS…………….

 

x is inversely proportional to y. x=80 while y=4. Find y when x is 8.