Answer:
2.4 hours or 2 hours and 24 minutes
Step-by-step explanation:
Jack mows 1/6 of the lawn per hour while Marilyn mows 1/4 of the lawn together. Adding up those rates yields in their combined mowing rate:
The time required for them to mow the entire lawn is:
It would take them both 2.4 hours to mow the lawn together.