By adding all of the amounts up: 75.00+55.25= 130.25, afterwords you need to add up the amount that Flynn spent, which is 25.15+18.65= 43.80, Once you have these two numbers. You need to subtract them from each other which looks like this: 130.25-43.80=86.45, then by subtracting that number from the last amount: 210.85-86.45=124.4.
The initial deposit is: 124.4
And to check your answer, you have to add 130.25+124.4=254.65, and then: 254.65-43.80= 210.85.