Question: How many races did Cale Yarborough win at an average speed of 88.924 mph?
Schema: create table table_22648285_1 (race_time varchar, driver varchar, average_speed__mph_ varchar, PRIMARY KEY (race_time))
SQL: select count(race_time) from table_22648285_1 where driver = "cale yarborough" and average_speed__mph_ = "88.924"