问题
解答题
简便计算
(1)300-123-77
(2)8.29+3.7+0.71+6.3
(3)125×898
(4)206×99+206.
答案
(1)300-123-77,
=300-(123+77),
=300-200,
=100;
(2)8.29+3.7+0.71+6.3,
=(8.29+0.71)+(3.7+6.3),
=9+10,
=19;
(3)125×89×8,
=(125×8)×89,
=1000×89,
=89000;
(4)206×99+206,
=256×(99+1),
=256×100,
=25600.