本同学计划5天装订本子300本，结果前3天装订了160本，后2听装订后还剩20本没完成，同学们在后2天共装订了多少本？5N+t+T/K9F5r4m:]0M8U7C/K(O9|+M2c
算式：提示9S.m4S8f:z5N+t+T/K9F5r4m:]0M8U7C/K(O9|+M2c
答：同学们在后2天共装订了:I9C*K7b3B'k-I.^本。5N+t+T/K9F5r4m:]0M8U7C/K(O9|+M2c