Answer:
3 hours 36min
Explanation:
In 1 hour,
Cory can complete 1/9 of the project
Lynn cna complete 1/6 of the project
Total: 1/9 + 1/6 = 5/18
time taken to complete the project together = 18/18 / 5/18 = 18/5 = 3 3/5 hours
3/5 hours = 36/60 hours = 36minutes
therefore, 3hours 36mins
Topic: Rates and Proportions
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