notam cu x = nr. moli 1-butena (CH2=CH-CH2-CH3)
si y = nr. moli 2-butena (CH3-CH=CH-CH3)
Cp Cs Ct
1-butena 1x 2x 1x
2-butena 2y 0 2y
x+2y/20 = 2x/1
=> x+2y = 40x => 39x = 2y => 19,5x = y
raportul molar 1-butena : 2-butena = x : y = x : 19,5x /:x
= 2 : 39