You earned a 90% on a science test yoy answer 18 questions correctly how many questions were on the test

Solve the following inequalities and show the solution on a number line. 3/4 (2x-7) ≤ 5

If the scale factor between two circles is 2x/5y what is the ratio of their areas?

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?