Question

几道数学题（四则混合运算）能简便的要简便！

1、3-1/3-1/3÷3 2、15/16+(7/16-1/4)÷1/2 3、1/5÷[(2/3+1/5)*1/13]

急啊啊！！！能简算的要简算！！要有过程，递等式。

Answer 1

1、3-1/3-1/3÷3
=3-1/3-1/9
=3-(3/9+1/9)
=23/9
2、15/16+(7/16-1/4)÷1/2
=15/16+3/16÷1/2
=15/16+6/16
=21/16
3、1/5÷[(2/3+1/5)*1/13]
=1/5÷[13/15*1/13]
=1/5÷1/15
=3

Answer 2

1、3-1/3-1/3÷3
=3-1/3-1/9
=3-(3/9+1/9)
=2又5/9
2、15/16+(7/16-1/4)÷1/2
=15/16+3/32
=33/32
3、1/5÷[(2/3+1/5)*1/13]
=1/5/[13/15*1/13]
=1/5/1/15
=3