Sam can mow 2 lawns in 3/4 hour. sam wants to mow 6 lawns on sunday so that he has enough money to buy a new video game. how long will it take him to mow 6 lawns?
i only have 10 minutes left,

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?