Answer: 7 7/8 hours long
Step-by-step explanation:
April worked 1 1/2 times as long as Carl did. 1 1/2 can be rewritten as 3/2. Number of Hours April worked on math project 3/2 times the Number of Hours Carl worked on Math project. Which Carl worked 5 1/4 hours long, which can be rewritten as 21/4