Question

1997×0.71+11×+2222×0.29=________．

Answer 1

2142
分析：根據(jù)題目可知，先把分?jǐn)?shù)化成小數(shù)，然后根據(jù)小數(shù)的巧算計算．0.71+0.29=1，可以把2222×0.29看成1997×0.29+225×0.29，因為7.25是0.29的25倍，11×7.25=10×7.25+7.25=72.5+0.29×25．
解答：
1997×0.71+11×+2222×0.29
=1997×0.71+11×7.25+2222×0.29
=1997×0.71+11×7.25+1997×0.29+225×0.29
=1997×（0.71+0.29）+225×0.29+10×7.25+7.25
=1997×（0.71+0.29）+225×0.29+72.5+0.29×25
=1997+72.5+0.29×（225+25）
=1997+72.5+72.5
=2142
故填：2142．
點評：此題主要考查的是小數(shù)的巧算，先把分?jǐn)?shù)化成小數(shù)7.25，然后根據(jù)小數(shù)的巧算技巧進(jìn)行脫式計算就可以了．