please complete as soon as possible and please do mot use excel formula

You plan to buy a house at $349,000. You only have 15% as a down payment and need to finance the remaining value with a 30 year 4.875% fixed-rate mortgage. If you expect your house to appreciate 3% annually, and you would like to refinance as soon as your loan balance falls below 80% of your house value, when would you expect to refinance? How about if you finance with a 15 year 4.25% fixed rate mortgage