15 Every child has multiple copies of 1. Seven children have two copies each, and the rest have two copies. Each of the six children has two books, and there are four more. Each of the nine children has a book, and there are seven books. 10 each child has six copies. 1 1 one for each child and five for each child. 12 each child has one book and more than four books. 13 children have three copies each, 14 children have two copies each.