(1/2+1/3+1/4)÷1/30+(1/3+1/5+1/7)÷1/105+(1/5+1/7+1/9)÷1/315

问题描述:

(1/2+1/3+1/4)÷1/30+(1/3+1/5+1/7)÷1/105+(1/5+1/7+1/9)÷1/315

(1/2+1/3+1/4)÷1/30+(1/3+1/5+1/7)÷1/105+(1/5+1/7+1/9)÷1/315
=[(6+4+3)/12]×30+[(35+21+15)/105]×105+[(63+45+35)/315]×315
=65/2+71+143
=246.5