Question

The quantities x and y are proportional.

x y

2 22

7 77

9 99


Find the constant of proportionality (r) in the equation: y = rx

r = ?

Thanks :)

Answer 1

r = 11

Explanation:

khan

Answer 2

r = 11

Explanation:

Given

The above table

y = rx

Required.

Find the constant of proportionality.

To find the constant of proportionality, we simply test the values of y and x in the given formula.

Using y = rx

Make r the subject of formula by dividing both sides by x

y/x = rx/x

y/x = r

r = y/x

From the above table of data;

When x = 2, y = 22

So, r = 22/2

r = 11

When x = 7, y = 77

So, r = 77/7

r = 11

When x = 9, y = 99

So, r = 99/9

r = 11

Notice that r maintains the value of 11 all through.

Hence, the constant of proportionality, r for the above data is 11