You are saving money to buy a house in 12 years, the estimated property price is $550,000. You aim to save sufficient funds to contribute to the 10% initial deposit, you parents have agreed to help you with 10% of the property cost, and you will arrange a mortgage to cover the remaining 80% of property cost. The nominal interest rate for your savings account is 12% per annum compounded quarterly. The nominal interest rate charged by the mortgage provider is 12% per annum compounded monthly.

a) Calculate the required size of week-end-saving instalments, so that you will have sufficient funds to pay the initial deposit for the property.