问题 解答题

丽丽遇到一道简算题,百思不得其解,你能帮帮她吗?

13.5×10.1+6.5×9.9.

答案

13.5×10.1+6.5×9.9,

=13.5×(10+0.1)+6.5×(10-0.1),

=13.5×10+13.5×0.1+6.5×10-6.5×0.1,

=(13.5+6.5)×10+(13.5-6.5)×0.1,

=20×10+7×0.1,

=200+0.7,

=200.7.

单项选择题
单项选择题