CREATE TABLE table_55433 ("Driver" TEXT, "Constructor" TEXT, "Laps" FLOAT, "Time/Retired" TEXT, "Grid" FLOAT)

what is the laps when the driver is tony rolt and the grid is less than 10?
SELECT SUM("Laps") FROM table_55433 WHERE "Driver" = 'tony rolt' AND "Grid" < '10'
SELECT SUM("Laps") FROM "table_55433" WHERE "Driver" = 'tony rolt' AND "Grid" < '10'