Emma buys 2 containers of milk every school day for lunch. She does not go to school on the weekends. How many containers of milk does she buy in 3 weeks?
There are 5 school days in a week: 5 days/week x 2 containers of milk/day = 10 containers of milk every week
Finally the number of container for 3 weeks is 3 weeks x 10 containers/week = <<3*10=30>>30 containers
#### 30