Did you know that spending a little time every day thinking through mind-challenging puzzles helps keep your mental processes sharp and agile well into old age? If you like good brainteasers and winning cool prizes as much as we do, we've got a neat little challenge for you to celebrate Train Your Brain Day! We've prepared three mental math/logic challenges designed to get your gray matter thinking creatively—give them a try and send in your solutions to email@example.com by October 23 for a chance to win one of two Mathnasium prize packs!
1. I am a 4-digit number. All of my digits are prime. I am an even number. None of my digits repeat. My tens place is greater than my ones and hundreds place combined. What number am I?
2. Using a 7-minute and a 5-minute timer, how can you measure 9 minutes?
3. You have 9 marbles: 8 weigh the same and 1 weighs slightly more than the others. You have a balancing scale. How can you find which marble is the heavy one with only 2 weighs?
And don’t forget—your brain craves variety, so once you've completed our challenge, be sure to mix up your daily brain training routine with a variety of mindteasers like Sudoku and crossword puzzles. Good luck!