加减混合计算24+48+17=2448+721897217++178989244872+1练一练8.852956-.85-29-48=练一练8529-56.5648-8.-4885+6-78+9-512-5+814-6+829-9+515+8-3口算6829-68-29+51=6829-39.3951+90139.+51901简便算法90356+24-30=67-34+29=做一做72-(47+16)=44716+1637263-9.932+(55-46)=5546-9+32414137+(50–26)70-(35+21)85-(32–18)32+(55-46)=76-(13+42)=做一做39561825+8-20476426332744613算一算25+36-47+58-23+19611472496849-25+18-38+78-6524424821764-(17+28)=291728+14526+(86-59)=53.8659-27+261536445-.19对不对?26+(40-8)70-(23+35)81-52+4865+18–3940+(56–29)36-(78-56)