A Venn diagram is a way of grouping different items ... contains everything we are interested in at that particular time. There’ll be circles inside the box which we use to group the items ...

A Venn diagram can show data ... is played by 20 people. 4 + 6 + 8 = 18, the Venn diagram only shows the data of 18 people. Assuming that the given data is correct, there should be 2 people ...