Sandra reads 5 books, Deacon read 6 books and Breanna read 7 books. One book was read by all three children, but every other book was different. How many different books did the children read?

16

Step-by-step explanation:

to begin with since one book is the same subtract 1 from each of the students total. this would leave you with 4, 5, and 6. Add these together and you get 15. Then you need to add back in the one book that they all read that was the same 15+1=16