98×0.51 40.7-2.6×9.3 0.8×2.4×12.5 的小数简便计算呵呵，不好意思，我会做了。麻烦这题，W▁▁▁you like to go s▁▁▁▁with us?Thanks giving Day in the USA is the f▁▁▁▁T▁▁▁▁in November.New Year's Day is the f▁▁▁▁day of the first m▁▁▁▁▁.是人教版的同步训练第3页第8题不知你们有没有
问题描述：
98×0.51 40.7-2.6×9.3 0.8×2.4×12.5 的小数简便计算
呵呵，不好意思，我会做了。
麻烦这题，
W▁▁▁you like to go s▁▁▁▁with us?
Thanks giving Day in the USA is the f▁▁▁▁T▁▁▁▁in November.
New Year's Day is the f▁▁▁▁day of the first m▁▁▁▁▁.
是人教版的同步训练第3页第8题
不知你们有没有
答
98/2+0.98
答
98×0.51=(100-2)×0.51=51-1.02=49.98
答
98×0.51
=98×（0.5+0.01）
=49+0.98
=49.98
40.7-2.6 *9.3
=40.7 -2.6*（10 -0.7）
=40.7 -26 +2.6*0.7
= 14.7 +2.6*0.7
=14.7 +2.6*（1 -0.3）
=14.7 +2.6 -0.78
=17.3-0.78
=16.52
0.8×2.4×12.5
=0.8×12.5×2.4
=10×2.4
=24
答
98×0.51 =100X0.51-2X0.51 40.7-2.6×9.3=40.7-2.6X(10-0.7)=40.7-26+2.6X0.7=14.7+2.3X0.7 =2.1X0.7+2.3X0.7 0.8×2.4×12.5 =(0.8X12.5)X2.4=10X2.4的小数简便计算