一道简便计算的题~想了半天想不出

(3/5+1/5)+(2/3-10/17)+(1/5+5/17)
=3/5+1/5+2/3-10/17+1/5+5/17
=(3/5+1/5+1/5)+2/3+(5/17-10/17)
=1+2/3-5/17
=51/51+34/51-15/51
=(51+34-15)/51
=70/51

(3/5+1/5)+(2/3-10/17)+(1/5+5/17)
=4/5+2/3-10/17+1/5+5/17
=(4/5+1/5)+2/3-(10/17-5/17)
=1+2/3-5/17
=5/3-5/17
=85/51-25/51
=60/51

(3/5+1/5)+(2/3-10/17)+(1/5+5/17)
=3/5+1/5+2/3-10/17+1/5+5/17
=(51+34-15)/51
=70/51

没什么简便算法
最多也就是去括号，重新组合，也就是用加法的结合律了。
不用想了。

(3/5+1/5)+(2/3-10/17)+(1/5+5/17)

=3/5+1/5+1/5-10/17+5/17+2/3

=1-5/17+2/3

=70/51

=60/51

70/51