According to question
[tex] 80\% of n = 72[/tex]
Change percentage to decimal by dividing it by 100
[tex] (80\div100)\mul n=72[/tex]
[tex]0.80\times n =72[/tex]
Now, crossmultiply we get,
[tex] n = \frac{72}{0.80}[/tex]
Now sloving we get
[tex] n = 90[/tex]
