Question

Working alone, Darryl can mop a warehouse in 11 hours. Elisa can mop the same warehouse in 9
hours. If they worked together how long would it take them?

Answer 1

Answer:

• ≈ 5 hours

Step-by-step explanation:

Time needed if they work together:

• 1 / (1/11 + 1/9) =
• 1/ (20 / 99) =
• 99/20 ≈ 5 hours