简算:2又4/5×23.4+11.1×57.6+6.54×28

问题描述:

简算:2又4/5×23.4+11.1×57.6+6.54×28

好难。。。⊙﹏⊙b汗,你几年的呀?

原式=
2.8×23.4+11.1×8×7.2+65.4×2.8=2.8×(23.4+65.4)+88.8×7.2
=2.8×88.8+88.8×7.2
=(2.8+7.2)×88.8
=10×88.8
=888

2.8×23.4+11.1×57.6+6.54×28=28×2.34+11.1×57.6+6.54×28=28×2.34+6.54×28+11.1×57.6=28×(2.34+6.54)+11.1×57.6=28×8.88+11.1×57.6=2.8×8×11.1+11.1×57.6=22.4×11.1+11.1×57.6=11.1×(22.4+57.6)=1...

2又4/5×23.4+11.1×57.6+6.54×28
=2.8×23.4+11.1×57.6+6.54×28
=28X2.34+6.54X28+11.1×57.6
=28X(2.34+6.54)+11.1×57.6
=28X8.88+11.1X57.6
=2.8X88.8+11.1×57.6
=2.8X8X11.1+11.1×57.6
=11.1X(22.4+57.6)
=11.1X80
=888