I need help with a Venn Diagram question. Oridnarily I know you would start in the middle but that is the piece that is missing in this problem. Can you please provide a formula to work this problem?

A recent survey of 150 people showed the following investments in stocks bonds and CODs

111 people invested in stocks

98 people invested in bonds

100 people invested in CODs

80 people invested in stocks and bonds

83 people invested in bonds and CODs

85 people invested in stocks and CODs

9 people did not invest in any of the three

How many people invested in all three