A Professional Basketball Player with a Poor Free Throw Percentage

Short Answer

A professional basketball player with a poor free throw percentage gets a personal coach to help him increase his percentage.He tells his coach that he has raised his proficiency from 70% to 90%.To see whether the athlete has improved,the coach asks the athlete to take 10 shots.He hits 10 out of 10.Suppose the athlete really is no better than before (still a 70% shooter).What's the probability that he could hit at least 10 out of 10 shots anyway?