Wendy noticed that out of 345 cars that passed by her house 56 were SUVs. About how many SUVs could she expect to see pass by if 2,100 cars were to pass her house?

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?