A machine to mill a brass plate has a setup cost of $700 and a unit cost of $4 for each plate manufactured. A bigger machine has a setup cost of $800 but a unit cost of only $1 for each plate manufactured. Find the break point. (Round your answer to the nearest whole unit.) Kyle estimates that it will take him 10 days to roof his house. A professional roofer estimates that it will take him 15 days to roof the same house. How long will it take if they work together? (Enter as improper fraction, not a mixed numeral)