Question - Calculating the Number of Mollies in a Pet Fish Collection

\text{Total pet fish} = 17

\text{Goldfish} = 7

\text{Let m be the number of mollies.}

\text{Total pet fish} = \text{Goldfish} + \text{mollies}

17 = 7 + m

m = 17 - 7

m = 10

\text{Levi has 10 mollies.}