Jack and Jill are saving money in the next 4 years for a deposit to buy their flat. They plan to put money into their bank account at the beginning of each year, starting at $20,000 with the amount growing at 10% each year.

If the bank pays an interest rate of 3% per annum, what would they have accumulated at the end of 4 years?

Please explain with growing annuity method and calculation. Thank you.