David typically takes 3 less hours than Marilyn to build a

Last updated: 5/20/2023

David typically takes 3 less hours than Marilyn to build a shelf if each works alone David and Marilyn worked together to build a shelf for 1 hour and then Marilyn finished the job without David after an additional 3 hours How long would it have taken David to build the shelf alone Do not include the units in your answer