-3/8-(+1/4)-(-1/2)-12/9-1又5/8+(-2又1/4)-(8又12/19)等于

问题描述:

-3/8-(+1/4)-(-1/2)-12/9-1又5/8+(-2又1/4)-(8又12/19)等于

-3/8-(+1/4)-(-1/2)-12/19-1又5/8+(-2又1/4)-(-8又12/19)
=(-3/8-1又5/8)+(-1/4-2又1/4+1/2)+(-12/19+8又12/19)
=-2-2+8
=4