1/3+3/4+3/20+19/50
=1/3+(15/20+3/20)+19/50
=1/3+9/10+19/50
=1/3+(45/50+19/50)
=1/3+32/25
=25/75+96/75
=121/75
=1又75分之46
1/3+15/20+3/20+19/50=1/3+18/20+19/50=1/3+9/10+19/50=10/30+27/30+19/50=37/30+19/50=1850/1500+570/1500=2420/1500=121/75
1/3+3/4+3/20+19/50
1/3+(1-1/4)+3/20+19/50
=1+(1/3-1/4+3/20)+19/50
=1+(20/60-15/60+9/60)+19/50
=1+7/30+19/50
=1+35/150+57/150
=1+92/150
=1+46/75
=1又(46/75)