We will consider the number to be [tex]n[/tex]. Based on the information in the problem, we can say that [tex]\frac{4}{9}n = 36[/tex]. By multiplying both sides by [tex]\frac{9}{4}[/tex], we get:
[tex]n = 36 \cdot \frac{9}{4} = 81[/tex]
The number is 81.
