Given that Leah's class collected 7 1/2 pounds.
Also it is mentioned that Rihanna's class collected 16 4/5 times as much as Leah's class,
[tex]\begin{gathered} \text{Rihanna's collection=16}\frac{4}{5}\text{ of Leah's collection} \\ \text{Rihanna's collection=16}\frac{4}{5}\times7\frac{1}{2} \\ \text{Rihanna's collection=}\frac{84}{5}\times\frac{15}{2} \\ \text{Rihanna's collection=}\frac{42}{1}\times\frac{3}{1} \\ \text{Rihanna's collection=12}6 \end{gathered}[/tex]Thus, Rihanna's class collected 126 pounds of food.
