If you spend money, you have less money than before. Subtraction is the operation that describes this "taking quantities away".
So, you start with 74$. You spend 24$, so we have to subtract 24:
[tex] 74-24 = 50 [/tex]
Then, you spend 21$. So, we have to subtract again:
[tex] 50-21 = 29 [/tex]
So, you're left with 29$ after you buy the video game and the groceries.
