A book company charges a shipping fee of $3 for the first item in a package, $2 for the second item and $1 for each additional item in the package. For example, the shipping fee charged for one package of four items is $3 + $2 + $1 + $1 = $7. How many dollars are saved by shipping 10 items in two packages of five items each, rather than five packages of two items each?