6-3/2-5/4-9/8-17/16-33/32
韩*** 2008-03-12 20:56:56 举报
6-3/2-5/4-9/8-17/16-33/32 =6-(1+1/2)-(1+1/4)-(1+1/8)-(1+1/16)-(1+1/32) =1-1/2-1/4-1/8-1/16-1/32 =1-(1/2+1/4+1/8+1/16+1/32) =1-31/32 =1/32
将所有分数都化为分母为32的分数.再用6减去它们的和即可.
1/5÷2/3=1/5×3/2=3/10小时
(38+41)x2.5=197.5千米
连接OC;∵AB=4,O是AB中点,且△ABC是直角三角形,∴OC=2...