a |---a---||---a---||---a---|
b |---a---|..28..| }1038
c |---a---|..28..||---a---|..28..|
in total avem 6 segmente egale
6a+28*3=1038
6a+84=1038
6a=1038-84
6a=954
a=159
primul are 159*3=477 lei
al doilea are 159+28= 187 lei
al treilea are 159+28+159+28=374 lei