A factory produces 2500 units of a product every day. How many units will it produce in 3 weeks if it operates 6 days a week?
First, let's find out how many days the factory operates in 3 weeks:

Days per week = 6
Weeks = 3

Total operating days = Days per week × Weeks
                                  = 6 × 3
                                  = 18 days

Now, we can find out how many units the factory produces in 18 days:

Units per day = 2500
Operating days = 18

Total units produced = Units per day × Operating days
                                     = 2500 × 18
                                     = 45,000 units

So, the factory will produce 45,000 units of the product in 3 weeks if it operates 6 days a week.