The constant of proportionality is equal to 9/8.
Proportionality relationship
The proportionality relationship between two factors is related to the value that one of the factors multiplies to become the other, so that:
[tex]a = k \times b[/tex]
Where K would be the proportionality constant.
Thus, to find the constant of the question, it is enough to relate the values as shown above, so that:
[tex]\frac{3}{4} = k \times \frac{2}{3}[/tex]
[tex]k = \frac{3}{\frac{4}{\frac{2}{3} } }[/tex]
[tex]k = \frac{9}{8}[/tex]
So, the proportionality constant is equal to 9/8.
Learn more about proportionality in: brainly.com/question/11263238