【采纳是一种美德】
简便计算:
1又2分之1加上2又6分至1加入3又12分之1加上4又20分之1
=(1+2+3+4)+(0.5+0.25+0.05)
=10.8
(1+2+3+4)+(1-1/2+1/2-1/3+1/3-1/4+1/4-1/5)
10+(1-1/5)
10又4/5
=(1+2+3+4)+(1/2+1/6+1/12+1/20)
=(1+2+3+4)+(1/2+1/2-1/3+1/3-1/4+1/4-1/5)
=10+(1/2+1/2-1/5)
=10+4/5
=10又4/5
等于1+2+3+4+1/2+1/6+1/12+1/20
=10+1/2+3/12+1/20
=10+3/4+1/20
=10+16/20
=10又4/5