计算下面各题
第一题13.5-3分之2*1+12分之5÷6分之1
13.5-(2/3)+(5/12)/(1/6)
解,得：
==13.5-(2/3)+(5/12)*6
==13.5-(2/3)+(5/2)
==13.5+2.5-(2/30
==11-(2/3)
==10又1/3
第二题8.75-【8分之5*（4分之3-20分之3）÷5分之4】
8.75-{(5/8)*[(3/4)-(3/20)]/(4/5)}
解,得：
==8.75-[(5/8)*(3/5)*(5/4)]
==8.75-(15/32)
==8.75-0.46875
==8.28125