解出下面四个简便计算题.
来源:学生作业帮助网 编辑:作业帮 时间:2024/11/07 19:30:36
解出下面四个简便计算题.
解出下面四个简便计算题.
解出下面四个简便计算题.
=(1+1/4+1/5+1/6+1/7)x(1/4+1/5+1/6)-(1/4+1/5+1/6+1/7)x[1+(1/4+1/5+1/6)]
=(1/4+1/5+1/6)+(1/4+1/5+1/6+1/7)x(1/4+1/5+1/6)-(1/4+1/5+1/6+1/7)-
(1/4+1/5+1/6+1/7)x(1/4+1/5+1/6)
=(1/4+1/5+1/6)-(1/4+1/5+1/6+1/7)
=37/60-[37/60+1/7]
=-1/7
2012÷2012又2012/2013
=2012÷[(2012x2013+2012)/2013]
=2012÷[(2012x2014)/2013]
=2012x[2013/(2012x2014)]
=2013/2014
2012÷2012又2012/2013
=1/[(2012又2012/2013)/2012]
=1/[(2012+2012/2013)/2012]
=1/(1+1/2013)
=1/(2014/2013)
=2013/2014
(4/9)x[3/4-(7/16-1/4)]
=(4/9)x[3/4-7/16+1/4]
=(4/9)x[1-7/16]
=(4/9)x[9/16]
=1/4
[14.8+(6又2/7-4.5)x1又3/25]+2又2/3
=[14.8+(6又2/7-4.5)x1又3/25]+2又2/3
=[74/5+(44/7-9/2)x28/25]+8/3
=[74/5+(44/7)x(28/25)-(9/2)x(28/25)]+8/3
=[74/5+(44)x(4/25)-(9)x(14/25)]+8/3
=[74/5+(176/25)-(126/25)]+8/3
=[74/5+2]+8/3
=[84/5]+8/3
=(252+40)/15
=292/15
=19又7/15
[14.8+(6又2/7-4.5)x1又3/25]+2又2/3
=[14.8+(6又2/7-4.5)x1又3/25]+2又2/3
=[14.8+(44/7-9/2)x28/25]+2又2/3
=[14.8+(44/7)x(28/25)-(9/2)x(28/25)]+2又2/3
=[14.8+(44)x(4/25)-(9)x(14/25)]+2又2/3
=[14.8+(176/25)-(126/25)]+2又2/3
=[14.8+2]+2又2/3
=[16.8]+2又2/3
=(16+2)+(4/5+2/3)
=18+(12+10)/15
=18+22/15
=18+1+7/15
=19又7/15
第二题=2013/2014
第三题=4/9-7/36=1/4