问题 解答题
①245-65-35②9.8+2.5+10.2+7.5③1.25×32×2.5.
答案

①245-65-35,

=245-(65+35),

=245-100,

=145;

②9.8+2.5+10.2+7.5,

=(9.8+10.2)+(2.5+7.5),

=20+10,

=30;

③1.25×32×2.5,

=1.25×(8×4)×2.5,

=(1.25×8)×(4×2.5),

=10×10,

=100.

单项选择题
单项选择题