Cinderella dreamed to go to the dance in the palace.  The Kind Fairy tried to assist her.   The problem was that the Kind Fairy had trouble remembering. That time the Fairy brought 3 packets with shawls for the Ball-dress. These packets were labelled as “not empty packet”, “golden shawl” and “silver shawl”. Regrettably, the Fairy had completely forgotten in which packet which shawl was. She remembered only that all titles were wrong. The worrying aspect was that as soon as one packet was opened, the others would disappear.
How can Cinderella choose the shawl for the golden dress?