=6.3×2.3+6.3×7.7=6.3×(2.3+7.7)=6.3×10=63
6.3×2.3+3×7.7×2.1=6.3x2.3+6.3x7.7=6.3x(2.3+7.7)=6.3x10=63
=6.3x2.3+6.3x7.7=6.3X(2.3+7.7)=6.3Ⅹ10=63
知道的都是学霸