Normal algorithm to find the number of books borrowed by at least one person:

A + B + C - (A B) - (B C) - (A C) + ( A, B, C)

Now, A, B, C, A, B, B, C, A and C are all known.

The number of books borrowed by at least one person is:

33+44+55-29-36-25+ (A, B, C)

=42+ (A, B, C)

A, B 29

A and C 25

B and C 36

Then the maximum number of books borrowed by A, B and C is 25

So the maximum number of books borrowed by at least one person is:< /p>

42+25=67 books

Then the books that have not been borrowed are at least:

100-67=33 books