(1/2+1/4+1/6+1/8)-(1/3+1/6+1/9+1/12)+(1/4+1/8+1/12+1/16)-(1/5+1/10+1/15+1/20）
=1/2×(1+1/2+1/3+1/4)-1/3×(1+1/2+1/3+1/4)+1/4×(1+1/2+1/3+1/4)-1/5×(1+1/2+1/3+1/4)
=（1/2-1/3+1/4-1/5）×(1+1/2+1/3+1/4)
=13/60×29/12
=377/720我看见了不同答案，你的答案正确吗？绝对正确啊