4-67 A man is buying a new eco-friendly electric riding mower. There will be no maintenance cost during the first 2 years because the mower is sold with 2 years free maintenance. For the third year, the maintenance is estimated at $100. In subsequent years the maintenance cost will increase by $50 per year.

(a) How much would need to be set aside now at 8% interest to pay the maintenance costs on the tractor for the first 6 years of ownership?

Can you please solve this using compound interest factors (P/A, P/G, Single Payment, Uniform Payment Series, Arithmetic Gradient)? The answer is supposed to be $483.26, but I keep coming up around $30 short.