Desiree rented a bicycle for $16.50 per hour. Her total rental fee was $49.50. Write and solve a multiplication equation to find the number of hours Desiree rented the bicycle for.

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?

If there are 3.281 feet in 1 meter, how many inches are in one centimeter

An engineer scale model shows a building that is 3 inches tall. if the scale is 1 inch = 600 feet, how tall is the actual building?