c1 = x , ms1 = S
c2 = 2x , ms2 = S
c.f. = 45% , ms.f.= 2S
aplicam regula dreptunghiului
c1= x -------------------------------> 2x-45 parti masa S1
c.f.= 45%
c2= 2x ----------------------------> 45-x parti masa S2
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total = 2x-45+45-x = x parti masa finala
x .................... 2x-45 parti masa S1 ................... 45-x parti masa S2
2S ............................. S ............................................ S
xS = 4Sx - 90S => x = 30% => c1 = 30%
c2 = 2x = 60%