(1/55+2/55+3/55+~+10/55)-(11/155+12/155+~20/55)用简便算法,
问题描述:
(1/55+2/55+3/55+~+10/55)-(11/155+12/155+~20/55)
用简便算法,
答
(1/55+2/55+3/55+~~~~~+10/55)-(11/155+12/155+~~~20/155)
=(1+10)*5/55-(11+20)*5/155
=1-1
=0