(87.65-19.36)-(47.15+11.64)怎麼簡便運算

(87.65-19.36)-(47.15+11.64)怎麼簡便運算


將公式猜分開87.65-19.36-47.15-11.64
公式中的數值取尾部積差取相同尾數方便計算(87.65-47.15)-(19.36+11.64)
87.65-47.15=40.5計算後小數點後面的差後兩位可以忽略一比特
19.36+11.64=31就算後小數點後面的和為零小數點後面的數值减少新增計算的效率
87.65-19.36)-(47.15+11.64)
=87.65-19.36-47.15-11.64
=(87.65-47.15)-(19.36+11.64)
=40.5-31
=9.5



99×89+89=簡便計算


99×89+89
=89×(99+1)
=89×100
=8900



89*9+99怎樣簡便計算


89*9+99
=89*9+89+10
=89*(9+1)+10
=890+10
=900



89.09+89.09×99簡便運算


89.09+89.09*99=89.09*(1+99)=89.09*100=8909



5.89+99×5.89用簡便運算


5.89+99×5.89
=5.89*(1+99)
=5.89*100
=589