The quantities xxx and yyy are proportional.

xxx yyy

888 1.61.61, point, 6

151515 333

222222 4.44.44, point, 4

Find the constant of proportionality (r)(r)left parenthesis, r, right parenthesis in the equation y=rxy=rxy, equals, r, x.

r=0.2

Step-by-step explanation:

Given the quantities x and y

When x=8, y=1.6

On Substitution into y=rx

1.6=8r

r=1.6/8=0.2

When x=15, y=3

On Substitution into y=rx

3=15r

r=3/15=0.2

When x=2, y=0.4

On Substitution into y=rx

0.4=2r

r=0.4/2=0.2

Therefore, the constant of proportionality, r=0.2

NOTE: One set of values is enough to determine this. Others are done for verification.