题目
脱式计算:
(1)
19.87- -( +8.87)
(2)
×4+ ×77
(3)
1.6×[1÷(2.1-2.09)]
答案: 19.87-913-(413+8.87) =19.87-913-413-8.87 =(19.87-8.87)-(913+413) =11-1 =10
2325 ×4+ 425 ×77 = 2325 ×4+ 7725 ×4 =4×(2325+7725) =4×4 =16
1.6×[1÷(2.1-2.09)] = 1.6×[1÷0.01] =1.6×100 =160