If a bag contains 100 red cubes, 50 blue cubes, 25 yellow cubes and 25 green cubes, what is the probability of Alicia choosing a blue cube?

You're locked out of your house. the only open window is on the second floor, 25 feet above the ground. there are bushes along the edge of the house, so you will need to place the ladder 10 feet from the house. what length ladder do you need to reach the window?