keywords: mortgage mortgages average raise house
text: Price of Average U.S. House Rises 8.5 Pct  WASHINGTON (Reuters) - The October average U.S. house price  jumped 8.5 percent from a year ago, setting the stage for  mortgage giants Fannie Mae and Freddie Mac to raise the limit  on mortgages they can buy, a Federal Housing Finance Board  survey showed on Tuesday.