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There was no better investment in my childhood than making me copy out times tables endlessly. Instead of being baffled by multiplication and division, I barely
by pessimizer 3y ago
There was no better investment in my childhood than making me copy out times tables endlessly. Instead of being baffled by multiplication and division, I barely think of it as math. Plenty of other adults I know can't divide no matter how much time they have, and it's a handicap in their social, professional, and political lives.
- agentgumshoe 3y agoHow often do you need to do that without a calculator (phone) at hand?
- Aeolun 3y agoBut it’s the principles that matter, not the tables. If you understand the principles you can easily figure out 563*3557. If you only know the tables you get stuck on 16x21. Though I agree that it’s convenient if multiplying anything under 10 is a idempotent action :)
- spywaregorilla 3y ago16 x 21 = (16 * 2 * 10) + 16 => (8 * 4 * 10) + 16 => 320 + 16 => 336 Is... that not how most people do mental math? I instinctively reduce everything to familiar patterns largely based on single digits numbers tables. 563 * 3557 is about 600 * 4000 => 6 * 4 * 100000 => about 2.4M Are other people doing the standard algorithm visualized somehow?
- tomp 3y agoI urge you to "figure out" 5633557 in base 9. Guess what? You'll first need to manually* derive the approximate "multiplication tables" (for individual digits), only then you'll be able to multiply multi-digit numbers.
- throwaway154 3y ago[dead]
- bonzini 3y agoMy son was doing additions and subtractions on his fingers until he had to learn multiplication tables. Until that point it hadn't clicked with him that you could also memorize the results! When forced to memorize multiplication results, he unconsciously started memorizing adds and subtracts as well.