Question

四年级下册数学简便计算和脱式计算各道两道

四年级下册数学简便计算和脱式计算各道两道

Answer 1

45.6×9.9
=45.6×（10-0.1）
=45.6×10-4.56
=456-4.56
=4551.44
45.6-0.99
=45.6-1+0.01
=44.6+0.01
=44.61
23.5×12.5×0.08
=23.5×（12.5×0.08）
=23.5×1
=23.5
0.623×2.4+6.23×0.76
=6.23×0.24+6.23×0.76
=6.23×（0.24+0.76）
=6.23×1
=6.23