A survey of 100 bank customers revealed that 58 of them have a savings account, 63 of them have a checking account, 22 of them have a savings account and a loan, 16 of them have a checking account and a loan, 27 of them have only a checking account, 12 have a savings account and a checking account and a loan. Assume that every customer has at least one of the services. How many customers have loan only?
