甲+乙+丙+丁=（23+30+27+25）÷3=35
甲=四数之和-乙丙丁的和=35-30=5
乙=四数之和-甲丙丁的和=35-27=8
丙=四数之和-甲乙丁的和=35-25=10
丁=四数之和-甲乙丙的和=35-23=12