Answer:
$510 is the amount she needs.
35*11 can reffer to a lot of things, let's suppose that she saves wins $35 and works 11 hours per day, so the amount would be equal to the amount of money that she wins per day.
Then the calculation
510/(35*11) would be equal to the amount of days that she needs to work to save the exact amount of 510 dollars, then this equation can help her.