1/2+1/6+1/12+1/20不用通分,能简算么
问题描述:
1/2+1/6+1/12+1/20不用通分,能简算么
答
可以
=1/1*2+1/2*3+1/3*4+1/4*5
=1-1/5
=4/5
答
1/2+1/6+1/12+1/20
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5
=1-1/5
=4/5