I need help with a practice question I’m stuck forgot the formula

Given:
[tex]15\div\frac{5}{7}[/tex]Required:
To find the quotient in the simplest form.
Explanation:
[tex]\begin{gathered} 15\div\frac{5}{7}=\frac{15}{\frac{5}{7}} \\ 15\div\frac{5}{7}=15\times\frac{7}{5} \\ 15\div\frac{5}{7}=\frac{105}{5} \end{gathered}[/tex]Now divide the number 105 by 5.
[tex]15\div\frac{5}{7}=21[/tex]Final Answer:
The quotient of the given expression is 21.