m(KHCO3) = 0,1*1,07*75 = 8,025 g
n(KHCO3) = 8,025/100 = 0,08025 mol
If m(CH3COOH) = x, then m(CH3CH2COOH) = (5,4 - x) g
Let's count the x.
x/60 + (5,4 - x)/86 = 0,08025
86x - 60x = 414,09 - 324
26x = 90,09
x = 90,09/26
x = 3,465
m(CH3COOH) = 3,465 g
m(CH3CH2COOH) = 5,4 - 3,465 = 1,935 g
w(X) = m(X)/m
w(CH3COOH) = 3,465/5,4 = 0,642 (64,2%)
w(CH3CH2COOH) = 1,935/5,4 = 0,358 (35,8 %)