The starting numbers are: 155 students enrolled; of them, 95 are males and the rest 155-95 = 60 are female. By the end of the semester, 0.6*95 = 57 male are still enrolled and 0.4*60 = 24 female are still enrolled. The number of those who still attend the class is 57 + 24 = 81 person. Hence, the percentage of the originally enrolled students withdrawn from the class is= 47.74. ANSWER