Julie takes her car to ABC garase for engine tune up The mec

Julie takes her car to ABC garase for engine tune up. The mechanic points out that it takes them an average of 40 min to complete the tune up. However Julie needs to pick up her daughter from school in 30 min. To be on time for her daughter, the car needs to be ready in 30 min. What is the probability Julie will be on time to pick up her daughter?