简便计算.(1)1357-5.8+327+4.2(2)7.7÷113+0.75×4310(3)(56-0.25+13)×2.4(4)212×4.625+638×250%-2.5.-数学
题文
简便计算. (1)13
(3)(
|
答案
(1)13
=(13
=17-5.8+4.2 =15.4; (2)7.7÷1
=7.7÷
=7.7×
=7.7×0.75+0.75×4
=0.75×(7.7+4
=0.75×(7
=0.75×12 =9; (3)(
=(
=
|
题文
简便计算. (1)13
(3)(
|
答案
(1)13
=(13
=17-5.8+4.2 =15.4; (2)7.7÷1
=7.7÷
=7.7×
=7.7×0.75+0.75×4
=0.75×(7.7+4
=0.75×(7
=0.75×12 =9; (3)(
=(
=
|