From 10:15 a.m. to 12:00 p.m. there are 1:45 hours. From 12:00 p.m. to 4:45 p.m. there are 4:45 hours therefore, each day Mr. Douglas works
hours.
Now, each week, Mr. Douglas works 4 days therefore, in one week, he works:
hours. Simplifying the above resut we get:
Finally, in four weeks Mr.Douglas works:
Answer: