解:
(1)原式
=(1/2+3/4+5/6)x24
=1/2x24+3/4x24+5/6x24
=12+18+20
=50
(2)原式
=1/2÷(2/3x6-1/4x6)
=1/2÷(4-2/3)
=1/2÷10/3
=1/2x3/10
=3/20 (20分之3)
五分之三除以[(五分之二+三分之一)除以二十五分之十一] 这些题要简便计算
(3)原式
=3/5÷[(2/5+1/3)x25/11]
=3/5÷[(6/15+5/15)x25/11]
=3/5÷(11/15x25/11]
=3/5÷5/3
=3/5x3/5
=9/25 (25分之9)