Step-by-step explanation
We can see in the Venn diagram the following facts:
As the number of students that just visited Spain is 5 because the statement says that 16 visited to Spain and we have in the Venn Diagram 5+4+2+?=16 visitors of Spain, the unknown value is equal to 5.
As the total number of students is equal to 37 and the number of students that have visited some of the three countries is equal to the sum of all the given numbers:
9+ 5 + 4 + 4 + 5 + 2 + 5 = 34 students
In conclusion, the number of students that have not been to Germany, Spain or France is 3