0.25+(-1/8)-(+7/8)-(+3/4)
=1/4-1/8-7/8-3/4
=2/8-1/8-7/8-6/8
=-3/2
=-1又1/2
-3-〔-5+(1-3*3/5)/(-2)〕
=-3-[-5+(-4/5)/(-2)〕
=-3-[-5+2/5]
=-3-[-23/5]
=-15/5+23/5
=8/5
=1又3/5
9又14/15*(-15)
=-149/15*15
=-149
-6²*(-1又1/2)²-3²/(1又1/2)三次方*3
=-36*9/4-9/(27/8)*3
=-81-8
=-89