We want to become millionaires attaining $1 million. Our 15th birthday is today, and our grandparents give us $20,000, which we invest at 10% interest rate. Additionally, they give us $3,000 for as long as we need it to attain our goal. Our retirement will start in 55 years last for 25 years and needs $50,000 per annum. In year 18, we take a vacation to the Greek islands, and it costs us $16,000. How old shall we be when we attain our goal?