The cost of tuition is $15000 per year. If her parents pay 70% of the tuition fee per year, It meansthat the amount that they would pay per year is
70/100 * 15000 = 10500
Since she will pay the rest, it means that the amount that she would pay is
15000 - 10500 = 4500
Given that she has one year to save this amount and there are 12 months in a year, then the minimum amount that she should save every month is
4500/12 = 375
The minimum amount that she should save each month is $375