To start, since she has been putting $175 in the bank for 10 months, then you can say that she has $1750 (or 10 times $175) of her $2475 from the deposits she has made.
Then since she has $2475 now , then she mus have started with $ 725 (OR $2475 -1750 = 725).
To create an equation for any number of months, we can let x represent the number of months and C represent the total in her account at any time.
The equation would be :
C = $175x + $725