If the flour to sugar ratio is 3 cups flour to 1 cup sugar, then how much sugar is needed if only 2 cups of flour are used? (give the answer as a fraction.)

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?

In a singing competition, there are 150 participants. at the end of each round, 40% of the participants are eliminated. how many participants are left after n rounds?

Simplify the expression below -3(10x+4y)+6(6x-2y)