A college student recently worked four weeks in a new summer job. In the fourth week, the student worked 20% more hours than in the third week. In the third week, the student worked 25% more hours than in the second week. In the second week, the student worked 40% more hours than in the first week. The student worked 42 hours in the fourth week on the job. How many hours did the student work in the first week on the job?

GMAT Problem-solving questions consist of topics such as arithmetic, algebra, geometry, and more. 
Approximately 18 – 20 questions are there.