Question

The quantities x and y are proportional

X= 8, 16, 32
Y= 2, 4, 8
Find the constant of proportionally (r) in the equation y= rx
r=
​

Answer 1

`r = (1)/(4)`

Explanation:

Given

The x and y values

Required

Determine the constant of proportionality

This is calculated from:

`y = rx`

Pick any corresponding x and y values:

`x = 8` and
`y = 2`

Substitute 8 for x and 2 for y in
`y = rx`

`2 = r * 8`

Make r the subject

`r = (2)/(8)`

`r = (1)/(4)`

Pick another x and y values:

`x = 16` and
`y = 4`

`r = (4)/(16)`

`r = (1)/(4)`

Hence, the constant of proportionality is 1/4