-14又3分之2+11又5分之2-(-12又3分之2)-14
=-14-2/3+11+2/5+12+2/3-14
=(-14+11+12-14)-2/3+2/5+2/3
=-5+2/5
=-4-5/5+2/5
=-4-3/5
=-4又5分之3