Răspuns :
a+b+c+d = 120
a - 5 = b :2 = 3×c = 2d
a - 5 = 2d a =2d +5
b:2 = 2d b = 2d×2 = 4d
a+ b +d = 2d +5 + 4d +d = 7d +5
a+ b+ c+d = 120 7d + c = 120 -5 = 115
3×c = 2×d c = 2d : 3 c = 2d/3 21d/3 + 2d/3 = 115
23d/3 = 115 d = 115×3 :23 = 345: 23 d = 15 a= 2×15 + 5 = 35
b = 4×15 = 60 c = 2×15: 3 = 10
a - 5 = b :2 = 3×c = 2d
a - 5 = 2d a =2d +5
b:2 = 2d b = 2d×2 = 4d
a+ b +d = 2d +5 + 4d +d = 7d +5
a+ b+ c+d = 120 7d + c = 120 -5 = 115
3×c = 2×d c = 2d : 3 c = 2d/3 21d/3 + 2d/3 = 115
23d/3 = 115 d = 115×3 :23 = 345: 23 d = 15 a= 2×15 + 5 = 35
b = 4×15 = 60 c = 2×15: 3 = 10