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| Thread ID: 68479 | 2006-04-30 09:11:00 | interesting math question | robsonde (120) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 450890 | 2006-04-30 10:49:00 | I guess it depends on which dictionary your reading :-) | gcarmich (10068) | ||
| 450891 | 2006-05-01 09:49:00 | Supplementary Question Why then is 1 not by definition a prime number? Answer: Because it has only one factor (itself or 1) and primes require exactly two factors. Another snippet: Many people use 22 / 7 as an approximation for pi. It is not particularly accurate and it is rational whereas pi is not. A better rational approximation of pi is actually 355 / 113. This one is accurate to about 6 decimal places. Now this retired maths teacher will vacate the chair and go back to sleep. Jim |
Hhel (8073) | ||
| 450892 | 2006-05-01 09:55:00 | A better rational approximation of pi is actually 355 / 113. This one is accurate to about 6 decimal places. Thanks a lot of this tip, Jim :thumbs: :D Cheers :) |
Renmoo (66) | ||
| 450893 | 2006-05-01 09:59:00 | That's OK James, Our daughter used to live just around the corner from you in Mahurangi Rd, (Dannemora) I think it was. They have, fortunately moved to the Kapiti Coast which is only 90 minutes away from here. Much more chance to see our grandchildren. The other two are in the Hutt Valley - wonderful. I don't usually spend all that much time on these forums - you are more likely to find me under the username jimwilk on the Xandros forums. I have even earned my Bronze badge there! (150 posts)! Jim |
Hhel (8073) | ||
| 450894 | 2006-05-01 10:49:00 | Well I for one enjoyed that. :thumbs: | Winston001 (3612) | ||
| 450895 | 2006-05-02 10:24:00 | Jameskan It was Matarangi Rd not Mahurangi. Jim |
Hhel (8073) | ||
| 450896 | 2006-05-02 10:33:00 | A little fact for the day for me :) Multiplying by 11: Easy to do for single digits, eg 8*11=88. Little hint for *most* 2 digit numbers... 11 times a 2 digit number, the answer is usually first number, sum of 2 numbers, second number. eg 11 * 23 = 253 (2, 2+3, 3) eg 11 * 72 = 792 (7, 7+2, 2) The problem is when the sum of the digits is greater than 9, then it becomes not so useful, but still quicker than working it out the usual way! 11 * 56 = 616 (5 (+1), 5+6, 6) (10 gets carried over one place) Too hard to try and explain that properly, so another example 11 * 68 = 748 Just something random I never got taught until 7th form :S |
roddy_boy (4115) | ||
| 450897 | 2006-05-02 12:00:00 | Jameskan It was Matarangi Rd not Mahurangi. Jim Hmmm, yeah. You told me once in an email when we were talking about Xandros and other Linux OS :D Also, thanks for the tip, Roddy boy. :thumbs: Cheers :) |
Renmoo (66) | ||
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