问题 解答题 口算. 50×8=540+450=720÷80=420÷30=125×8=653-52=530×3=369÷9= 答案 50×8=400,540+450=990,720÷80=9,420÷30=14,125×8=1000,653-52=601,530×3=1590,369÷9=41.故答案为:400,990,9,14,1000,601,1590,41.