甲乙丙丁a,b,c,d
假设m=a+b+c+d
a=1/2(b+c+d)=1/2m-1/2a
b=1/3(a+c+d)=1/3m-1/3b
c=1/4(a+b+d)=1/4m-1/4c
d=60
a=m/3,b=m/4,c=5/m
d=m-(a+b+c)=m-m(1/3+1/4+1/5)=60
m=3600/13
所以:
甲乙丙丁的和为3600/13
甲乙丙丁a,b,c,d
假设m=a+b+c+d
a=1/2(b+c+d)=1/2m-1/2a
b=1/3(a+c+d)=1/3m-1/3b
c=1/4(a+b+d)=1/4m-1/4c
d=60
a=m/3,b=m/4,c=5/m
d=m-(a+b+c)=m-m(1/3+1/4+1/5)=60
m=3600/13
所以:
甲乙丙丁的和为3600/13