We can calculate the balance at each line by adding (or substracting, if that was the case) from the balance of the previous row.
The items that are "check" and "service charge" will substract from the balance, while the items that are "deposit" will add to the balance.
Then, we can calculate the balance in the second row B_2 as:
[tex]B_2=B_1+a_2=109.32-15.41=93.91[/tex]
We can iterate this process for all the rows and we will get:
For the last row, the data we need to calculate is the variation between balances.
We can do that as:
[tex]\begin{gathered} B_9=B_8+a_9 \\ a_9=B_9-B_8=58.06-83.65=-25.59 \end{gathered}[/tex]
