第一题:(41+1/3)*3/4=(40+1+1/3)*3/4=(40+4/3)*3/4=30+1=31
同理,式子=31+41+51+61=184
第二题:1-2/3=1/3=3/9
3/9-2/9=1/9=3/27
3/27-2/27=1/27=3/81
……
最后3/729-2/729=1/729
原题=41*3/4+51*4/5+61*5/6+1/4+1/5+1/6
=40*3/4+3/4+50*4/5+4/5+60*5/6+5/6+1/4+1/5+1/6
=30+40+50+1+1+1=123
原题=1/3-2/9-2/27-2/81-2/243-2/729
=1/9-2/27-2/81-2/243-2/729
=以此类推=1/729
1 原式=(123/3+1/3)*3/4+(204/4+1/4)*4/5+(305/6+1/5)*5/6
=124/3 * 3/4+ 205/4 * 4/5 + 306/5 * 5/6
=31+41+51=123
2 原式=1/3-2/9-2/27-2/81-2/243-2/729
=3/9-2/9-...
=3/27-..
=1/729