3.71+3.71X7.4-8.4X3.71=3.71X1+3.71X7.4-8.4X3.71=3.71X(1+8.4-7.4)=3.71X2=7.421.2+8.8×1.25=1.2+(8+0.8)x1.25=1.2+(8x1.25+0.8x1.25)=1.2+(10+1)=12.216.2÷[64.8-(51.3-2.7)]=16.2÷(64.8-51.3+2.7)=16.2÷16.2=1
关于植树节的童谣2首
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