Three instructors in a coordinated course, T1, T2, and T3evaluates axam papers. T1 evaluates 20% of the exam papers, T2pevaluates 30% and T3 evaluates 50%. The three theachers make thefollowing proportions of errors (E) while evaluating the exampapers: 0.008, 0.008, and 0.003 respectively. If a randomlyselected exam paper has an error (E), what is the probability it isfrom instructor T1?
