1-(1/4-1/8)-(1/8-1/16)-(1/16-1/32)
1/20+1/30+1/42+1/56+1/72+1/9
5/8乘[ ( 2又1/3-1.2)/34%乘3/5-0.4
1-(1/4-1/8)-(1/8-1/16)-(1/16-1/32)
1/20+1/30+1/42+1/56+1/72+1/9
5/8乘[ ( 2又1/3-1.2)/34%乘3/5-0.4
1-(1/4-1/8)-(1/8-1/16)-(1/16-1/32)
=1-1/4+1/8-1/8+1/16-1/16+1/32
=1-1/4+1/32
=25/32
1/20+1/30+1/42+1/56+1/72+1/9
=1/4×1/5+1/5×1/6+1/6×1/7+1/7×1/8+1/8×1/9+1/9
=1/4-1/5+1/5-1/6+1/6-1/7+1/7-1/8+1/8-1/9+1/9
=1/4
5/8×[( 2又1/3-1.2)÷34%×3/5-0.4]
=5/8×[(2又1/3-1又1/5)÷17/50×3/5-2/5]
=5/8×[17/15÷17/50×3/5-2/5]
=5/8×[2-2/5]
=5/8×8/5
=1