Răspuns
Explicație pas cu pas:
0,(3)= 3/9=1/3
0,25= 25/100=1/4
0,2= 2/10= 1/5
(a+b); (b+c) ; (c+a) ip cu 1/3 ; 1/4; 1/5
(a+b) * 1/3 = (b+c) * 1/4 = (c+a) * 1/5 =k
(a+b)/3= (b+c)/4 = (c+a)/5=k
a+b=3k
b+c=4k
c+a=5k
2a+2b+2c=3k+4k+5k
2(a+b+c)= 12k |:2
a+b+c=6k
c= 6k-3k
c=3k
a=6k-4k
a=2k
b=6k-5k
b=k
a³ * 2b⁴ * c² =72
(2k)² * 2k⁴ * (3k)² =72
4k² * 2k⁴ * 9k² =72
72k⁸ =72
k⁸=1 =>k=1
a=2*1=2
b=1
c=3*1=3
