Answer:
6.5
Step-by-step explanation:
Proportional relationship:
[tex]y \propto x \implies y=kx[/tex]
where k is the (non-zero) constant of proportionality.
To determine the constant of proportionality, substitute the given values into the equation and solve for k:
[tex]\implies 19.50=3k[/tex]
[tex]\implies k=6.5[/tex]
Therefore, the constant of proportionality is 6.5.