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Help
If you have any questions, you are always welcome to contact us. We'll get back to you as soon as possible, withing 24 hours on weekdays.
Customer service
All questions about your order, return and delivery must be sent to our customer service team by e-mail at yourstore@yourdomain.com
Sale & Press
If you are interested in selling our products, need more information about our brand or wish to make a collaboration, please contact us at press@yourdomain.com
Follow the hour hand and minute hand of a clock for 24 hours. How many times do they form a right angle?Timothy's house has several rooms, each of which has an even number of doors, including doors that lead outside. Is the number of outside doors even or odd?Stimulating and delightful, this collection of puzzles features original and classic brainteasers. The author, a puzzle columnist for Le Monde, specially selected these mindbenders for the widest possible audience, ensuring that they're neither too hard for those without a math background nor too easy for the mathematically adept. All puzzles are clearly stated and accurately answered at the back of the book and they're great fun to consider, whether you crack them or not. Includes a Foreword by Martin Gardner.
⚠️ WARNING (California Proposition 65):
This product may contain chemicals known to the State of California to cause cancer,
birth defects, or other reproductive harm.
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⚠️ California Proposition 65 Warning: Some products sold on this website may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.
