=（12.5×0.8）×6.78=10×6.78=67.8
12.5x6.78x0.8=12.5x0.8x6.78=10x6.78=67.8
12.5*6.78*0.8=(12.5*0.8)*6.78=10*6.48=67.8
12.5×6.78×0.8=12.5×0.8×6.78=10×6.78=67.8
12,5x0.8x6.78=10x6.78=67.8
