Given
Sugar = 3/4
Cinnamon = 3/5
Ground Nutmeg = 1/8
Salt = 1/4
Find
Proportion for 20 people
Explanation
Given data is for 6 servings 
For 20 servings - 3 complete servings and one 1/3 rd serving
[tex]\begin{gathered} Sugar=\frac{3}{4}\times3+\frac{1}{3}\times\frac{3}{4}=\frac{10}{4}=\frac{5}{2} \\  \\ Cinnamon=\frac{3}{5}\times3+\frac{1}{3}\times\frac{3}{5}=\frac{10}{5}=2 \\  \\ GroundNutmeg=\frac{1}{8}\times3+\frac{1}{3}\times\frac{1}{8}=\frac{10}{24}=\frac{5}{12} \\  \\ Salt=\frac{1}{4}\times3+\frac{1}{3}\times\frac{1}{4}=\frac{10}{12}=\frac{5}{6} \\  \end{gathered}[/tex]
Final Answer
Hence , the above is the required answer.