问题 解答题
用简便方法计算:
1.29+3.7+0.71+6.3

528×78+472×78
答案

(1)1.29+3.7+0.71+6.3

=(1.29+0.71)+(3.7+6.3),

=2+10,

=12;

(2)528×78+472×78

=(528+472)×78,

=1000×78,

=78000;

单项选择题
单项选择题