手脑速算教程及练习(14)

63+17-43-18-11=                           16+36-33+50+4=

60-25+44-18+21=                          78-13-19+35-32=

26+38-36+17-9=                          19+36+33-50-24=

61-35+44+18-21=                          63-35+32-13-19=

70-53+25+13-46=                          17+19+18-26-20=