ms1 = 200g, c1% = 38%
ms2 = 140 g, c2% = 60%
stim ca ms.final = ms1+ms2 = 200+140 = 340g
c% = mdx100/ms
=> md1 = ms1xc1/100 = 200x38/100 = 76g
=> md1 = ms2xc2/100 = 140x60/100 = 84g
=> md.final = md1+md2 = 76+84 = 160g
=> cx%final = md.finalx100/ms.final
= 160x100/340 = 47%