The daughter should pick envelope 1. Unfortunately she picked envelope 3. Statements 1 and 2 were false, and the only true statement was statement 3. If the check was in envelope 1, that would make statement 1 false, statement 2 false and statement 3 is the only true statement. If the check was in envelope 2, statements 1 and 2 would both be true. If the check was in envelope 3, statements 1 and 3 would both be true.