【(+3/5)+(-1/2)+(-5/12)】*60
=[3/5-1/2-5/12]*60
=36-30-25
=-19
(-11)*(-2/5)+(-11)*(+2又3/5)+(-11)*(-1/5)
=11*(2/5-13/5+1/5)
=11*(-2)
=-22