56.5x9.9+5.65的简便算式56.5x9.9+5.65的简便算式56.5x9.9+5.65的简便算式56.5×9.9+5.65=5.65×99+5.65=5.65×(99+1)=5.65×10
小数乘法的简便计算56.5x9.9+56.5小数乘法的简便计算56.5x9.9+56.5小数乘法的简便计算56.5x9.9+56.556.5×9.9+56.5=56.5×(10-0.1)+56.5=5
9x99x99x99×9=819×9------81如果看不明白就九个九相加9+9+9+9+9+9+9+9=81验算的话:81÷9=99x9=819x9是9个9,因为8个9是72,再加一个9就是81了
3.228x(-9)+(-3.272)x9-(-1.5)x93.228x(-9)+(-3.272)x9-(-1.5)x93.228x(-9)+(-3.272)x9-(-1.5)x9仔细观察,可以将式子
2.34x9.9+0.2342.34x9.9+0.2342.34x9.9+0.2342.34x9.9+0.234=2.34x9.9+2.34x0.1=2.34x(9.9+0.1)=2.34x10=23
5.9x9.9+0.59怎么简算5.9x9.9+0.59怎么简算5.9x9.9+0.59怎么简算5.9x9.9+0.59=5.9x9.9+5.9x0.1=5.9(9.9+0.1)=5.9x10=59
9+9x9= ( )+( )x9=900000 18+98x9= ( )+( )x9=9000000 117+987x9= ( )+( )x9=90000000找规律
9+9x9=()+()x9=90000018+98x9=()+()x9=9000000117+987x9=()+()x9=90000000找规律9+9x9=()+()x9=90000018+98x9=
0.8x33x1.257.2x9.90.8x33x1.257.2x9.90.8x33x1.257.2x9.90.8x33x1.25=4/5×5/4×33=1×33=337.2x9.9=7.2×(10-
19+9 X9=100 118+98X9=1000 117+987X9=10000 116+98719+9 X9=100118+98X9=1000117+987X9