13.9×5.43+13.9×5.43 =2×(13.9×5.43) =2×13.9×5.43 =27.8×5.43 =120.954 或者 13.9×5.43+13.9×5.43 =13.9×(5.43+5.43) =13.9×10.86 =150.954