Kelly bought 3 movie tickets and spent $39.60. each ticket cost the same amount. which equation can be used to solve for p, the amount each ticket cost? a. 3+p= 39.60
b. p-3= 39.60
c. 39.60=30
d. 39.60 = p/3

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?