问题 解答题 口算.17+9=20+70=18+26=56+44=60-25=180-5=330-30=49-9= 答案 17+9=26,20+70=90,18+26=44,56+44=100,60-25=35,180-5=175,330-30=300,49-9=40.故答案为:26,90,44,100,35,175,300,40.