Răspuns:
Explicație pas cu pas:
a = primul numar
a = b : 2
b = 2c
c = 3d
________
c = 3d
b = 2*3d = 6d
a = 6d : 2 = 3d
(a + b + c + d) : 4 = 6,695
a + b + c + d = 6,695*4 = 26,78
3d + 6d + 3d + d = 26,78
13d = 26,78
d = 26,78 : 13 = 2,06
a = 2,06*3 = 6,18
b = 2,06*6 = 12,36
c = 2,06*3 = 6,18