Bani simona = a
Bani mihai = b
a + b = 75
a : b supra 2 = 3,5
a = 3,5 x b supra 2
a = 3,5b supra 2
a + b = 75
3,5b supra 2 + b = 75
Amplificam b cu doi
3,5b supra 2 + 2b supra 2 = 75
5,5b supra 2 = 75
75 x 2 = 5,5b
150=5,5b
b = 150 : 5,5
b = 27,27
a = 75 - 27,27
a = 47,73