198÷21≈( )
运用加法的交换律和结合律的是( )A.5.84+0.78+4.16="5.84+4.16" +0.78 B.5.84+0.78+4.16=0.78+(5.84 +4.16) C.5.84+0.78+4.16=5.84+(0.78 +4.16)
对算式15.73-(6.25+3.73)计算方法较简便的是( )A.15.73-6.25-3.73 B.15.73-3.73-6.25
对算式80.41-(6.28+25.41)-3.72计算方法简便的是( )A.80.41-25.41-(6.28+3.72) B.80.41-25.41-6.28-3.72
对算式6.67+0.49-3.67计算方法简便的是( )A.6.67-3.67+0.49B.6.67+(0.47-3.67)
运用加法运算定律,使(8.28+2.69)+4.72运算简便的计算过程是( )A.(8.28+2.69)+4.72 =(8.28+4.72)+2.69 =13+2.69 =15.69B.(8.28+2.69)+4.72 =8.28+2.69+4.72 =10.97+4.72 =15.69C.(8.28+2.69)+4.72 =2.69+8.28+4.72 =2.69+13 =15.69