Here the sets are overlapping. Overlapping sets are those which contain at least one element common.
The four sets of coffee, tea, chocolate and cocoa users all are overlapping containing one or more elements of the other.
The missing set numbers have been marked as a, b, c, d in the diagram.
The data in the question tells that
60 take coffee,
30 take coffee only
2 take tea, coffee and Chocolate,
whereas 12 take tea and coffee
17 take tea only,
2 take tea, coffee and Chocolate,
3 take chocolate, tea and cocoa,
whereas 12 take tea and coffee
36 take tea,
9 take tea and chocolate
47 take chocolate only
7 take chocolate and cocoa
3 take chocolate, tea and cocoa,
2 take tea, coffee and Chocolate,
9 take tea and chocolate
20 take cocoa only
27 take cocoa
3 take chocolate, tea and cocoa,
7 take chocolate and cocoa
Total tea takers= T= { 17+12+9+2+3+a+b}= {43+a+b}
Total coffee takers= C= {30+12+2+a+b+c+d}= {44+a+b+c+d}
Total Chocolate users= Ch= {47+9+3+2+7+b+c} = {68+b+c}
Total Cocoa users= Co= { 20+7+3+a+b+c+d}= {30+a+b+c+d}
C∩ Co= {d}
C∩ T= {12}
T ∩ Ch= {9}
Ch∩ Co= {7}
This can be shown by the Venn diagram as follows.
