1.用简便方法计算:99又17/18 × (﹣9) 2.﹣4 - [﹣5 +﹙0.2 × 1/3 - 1﹚ ÷ ﹙﹣1又2/5﹚] 3.|﹣9/41| - |﹣13/14| + |9/41 - 13/14| 注:| | 为绝对值的符号
问题描述:
1.用简便方法计算:99又17/18 × (﹣9) 2.﹣4 - [﹣5 +﹙0.2 × 1/3 - 1﹚ ÷ ﹙﹣1又2/5﹚] 3.|﹣9/41| - |﹣13/14| + |9/41 - 13/14| 注:| | 为绝对值的符号
答
用简便方法计算:
99又17/18 × (﹣9)
=-(100-1/18)*9
=-900 +1/2
=-899又1/2
2.﹣4 - [﹣5 +﹙0.2 × 1/3 - 1﹚ ÷ ﹙﹣1又2/5﹚]
=-4+5+14/15*5/7
=1+2/3
=5/3
3.|﹣9/41| - |﹣13/14| + |9/41 - 13/14|
=9/41-13/14+13/14-9/41
=0