Can you solve it? Are you smarter than a Navy admiral?

"You are an admiral in the Navy, in charge of an important mission. You have two choices. a) To send a single ship whose chance of success is P per cent. b) To send two ships, each of whose chance of success is P/2 per cent. At least one ship needs to be successful for the mission to be a success. Which is your best option?"

"Before you are two oracles, Randie and Rando, who will answer yes or no to any question you ask. Randie answers yes or no at random to all questions. Rando decides at random whether to tell the truth or to lie for each question, and then answers the question accordingly. Is there a way to tell them apart? If so, what is it?"

"Johnny's homework is to calculate 5548-5489. The answer is 59. He figured that the 548 cancelled out, leaving 59. He tested the technique again. He typed in a subtraction of the form XXYZ - XYZW where X, Y, Z and W were distinct digits, and found out it was indeed XW!"

Tanya Khovanova, a prominent figure in recreational mathematics, has co-authored a book titled Mathematical Puzzles and Curiosities with Ivo David and Yogev Shpilman. The book includes a variety of engaging puzzles, such as a decision-making scenario involving naval ships, a challenge with two oracles, and a mathematical error made by a student. Each puzzle presents unique twists and encourages critical thinking. The book aims to entertain and educate puzzle enthusiasts, showcasing Khovanova's contributions to the field.

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