Let's assume that your income is 100 units for simplicity.
You save 30%, which is 30 units, leaving you with 70 units.
You then use 10% of the reminder (70 units), which is 7 units, for internet purchases.
So the total amount you have spent on saving and internet purchases is 30 + 7 = 37 units.
The remaining amount for other purposes is 100 - 37 = 63 units.
Therefore, the percentage of your income that is left for other purposes is:
63 / 100 x 100% = 63%.
So, 63% of your income is left for other purposes after saving 30% and spending 10% of the reminder on internet purchases.