In his new living room, kirk installed carpeting on 1/2 of the floor and tile on another 1/4 of the floor. what fraction of the floor is now covered by either carpet or tile?

What is the result of adding the system of equations? 2x+y=4 3x-y=6

What is the greatest number of parts of a circle that can be formed by cutting the circle with 7 straight cuts? (note: the parts do not have to be equal in size)

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?