Radian Guaranty, the nation’s second largest mortgage insurer in terms of new policies written, late this week reached an agreement with Freddie Mac, limiting its exposure on a group of 25,760 legacy loans to $840 million. In a new filing with the Securities and Exchange Commission, the publicly traded MI said it expects to record a loss of $20 million in the third quarter because of the settlement. The Radian-guaranteed mortgages were delinquent as of the end of 2011. The MI has already paid $632 million to cover loss claims on these loans through two different payments. It also had set aside $205 million in a collateral account to cover what it calls “loss mitigation activity” on the notes.