50-49-48+47+46+45+44+43-42-41-40+39+98怎么简算呀?

问题描述:

50-49-48+47+46+45+44+43-42-41-40+39+98怎么简算呀?

(50-40)+(-49-41-48-42)+(47+43+46+44)+45+39+38=10+45+39+38=132

50-(49+41+48+42)+(47+43)+(46+44)-40+45+39+1+98+2-3
=50-180+180-40+140-3
=147