Ten numbered balls are placed in a box. The balls numbered 1–4 are blue and those numbered 5–10 are red. What is the probability that a ball drawn at random from the box is blue?

Zachary has been trying to work on an essay for almost three hours, be he can't seem to focus for more than 15 or 20 minutes at a time. what should he do so that the quality of his work doesnt suffer because of poor concentration and lack of energy