CREATE TABLE table_20508 ("Region of USSR" TEXT, "Number of families" FLOAT, "Number of people" FLOAT, "Average family size" TEXT, "% of total deportees" TEXT)

What is the most number of families in regions where average family size is 2.7?
SELECT MAX("Number of families") FROM table_20508 WHERE "Average family size" = '2.7'
SELECT MAX("Number of families") FROM "table_20508" WHERE "Average family size" = '2.7'