甲乙丙总数为4.25×3=12.75丙数为总-甲-乙即12.75-4.5-5.3=2.95
4.25x3=12.7512.75-4.5-5.3=2.95答:丙是2.95.
已知甲、乙、丙三数的平均数是4.25,又知甲数是4.5,乙数是5.3,求丙数。4.25×3=12.7512.75-4.5-5.3=2.95(丙)
4.25*3-4.5-5.3=2.95
4.25*3=12.7512.75-4.5-5.3=2.95