问答题
(1)6.80x103-20= (2)7.234+20-5.28= (3)172.0347+2.1+70-0.01= (4)5.231x2.0÷10=
问答题 （1）76.9÷10+2.3= （2）（5.002-4.002）3.002= （3）（2.480-2.2）x5.989= （4）2.00x4.00+50.0x1.00-20x0.1=
问答题 (2)72.347+5.32-0.137= (3)8.793x3.5÷200= (4)8.7x102-1.7x101
问答题 (1)68.457+236.51-9.753=
