noel shelley | 24/08/2021 13:19:27 |
2308 forum posts 33 photos |
Edited By noel shelley on 24/08/2021 13:20:34 |
Michael Gilligan | 24/08/2021 13:49:08 |
![]() 23121 forum posts 1360 photos | Brilliant MichaelG. |
Nigel Graham 2 | 24/08/2021 15:04:06 |
3293 forum posts 112 photos | Hee-hee! I like it! I'm baffled by the 5 o'clock one though. How does the square-root of 9! = 6 as I read it; or come to that the square-root of 8! = 5? Nor does it work by the factorial of the square-root of nine. |
duncan webster | 24/08/2021 15:12:57 |
5307 forum posts 83 photos | (sqrt(9))! - 9/9 3! - 1 3*2*1 - 1 =5 Does Bodmas cover factorials? Edited By duncan webster on 24/08/2021 15:14:08 |
Ramon Wilson | 24/08/2021 15:35:43 |
![]() 1655 forum posts 617 photos | Ah! you'd need a calclator to turn that into real time Nice one Noel
Tug |
Nicholas Farr | 24/08/2021 15:39:18 |
![]() 3988 forum posts 1799 photos | Hi Noel, very good, however I've not had course to come across the type of equations for 5, 7 or 9, the 7 one taken the longest time for me to figure out on one of my fraction capable calculators. Regards Nick. |
SillyOldDuffer | 24/08/2021 15:40:42 |
10668 forum posts 2415 photos | If you got 601.3952191045344 for 5O'Clock, join my club. Also, am I right in saying that the digits of the hours expressed in seconds always add up to 9? e.g.: 1AM = 3600s so 3+6+0+0 = 9 4AM = 14400 so 1+4+4+0+0 = 9 9AM = 32400s so 3+2+4+0+0 = 9 11AM = 39600s so 3+9+6+0+0 = 18 & 1+8 = 9 Bound to be useful for something. Is there a prize? Dave |
Journeyman | 24/08/2021 15:52:00 |
![]() 1257 forum posts 264 photos | I agree, the 5 is a bit iffy, needs brackets as per Duncan's explanation. If you fancy the real thing for your workshop wall available at a nearby South American rain-forest for about 15quid. John |
Nigel Bennett | 24/08/2021 17:08:10 |
![]() 500 forum posts 31 photos | I'm sure there must be a much simpler expression for the 9 o'clock position, but I can't imagine what... |
Ady1 | 24/08/2021 17:32:02 |
![]() 6137 forum posts 893 photos | cool! Engineers or mathematicians xmas pressie sorted too |
Michael Gilligan | 24/08/2021 19:47:10 |
![]() 23121 forum posts 1360 photos | Posted by Journeyman on 24/08/2021 15:52:00:
I agree, the 5 is a bit iffy, needs brackets as per Duncan's explanation. . I suppose it’s fair … given that the ‘bang’ is outside the sqrt sign MichaelG. |
duncan webster | 24/08/2021 19:51:16 |
5307 forum posts 83 photos | pressed the wrong button
Edited By duncan webster on 24/08/2021 19:51:55 |
Brian G | 24/08/2021 20:36:59 |
912 forum posts 40 photos | Posted by SillyOldDuffer on 24/08/2021 15:40:42:
If you got 601.3952191045344 for 5O'Clock, join my club. Also, am I right in saying that the digits of the hours expressed in seconds always add up to 9? e.g.: 1AM = 3600s so 3+6+0+0 = 9 4AM = 14400 so 1+4+4+0+0 = 9 9AM = 32400s so 3+2+4+0+0 = 9 11AM = 39600s so 3+9+6+0+0 = 18 & 1+8 = 9 Bound to be useful for something. Is there a prize? Dave Probably been won almost as soon as we started using base 10 with arabic/indian numerals Dave, as the sum of the digits of any multiple of 9 is always a multiple of 9, and 3600 = 400 x 9. I just checked and the same thing seems to work in other bases such as Hex, so that the digits of multiples of F add up to multiples of F. I'm beginning to understand why I was put in the applied maths stream at school as this sort of thing just confuses me. Brian G Edited By Brian G on 24/08/2021 20:37:57 |
pgk pgk | 24/08/2021 20:54:25 |
2661 forum posts 294 photos | Trachtenberg speed system multiplying by 9 https://en.wikipedia.org/wiki/Trachtenberg_system#Multiplying_by_9 pgk |
Nicholas Farr | 24/08/2021 21:36:46 |
![]() 3988 forum posts 1799 photos | Posted by Michael Gilligan on 24/08/2021 19:47:10:
Posted by Journeyman on 24/08/2021 15:52:00:
I agree, the 5 is a bit iffy, needs brackets as per Duncan's explanation. . I suppose it’s fair … given that the ‘bang’ is outside the sqrt sign MichaelG. Hi, this is how I did it on my calculator. This is the only way I could get it on my calculator with any brackets, any other combination of brackets gave a wrong answer or a system error. Regards Nick. Edited By Nicholas Farr on 24/08/2021 21:37:38 |
Nigel Graham 2 | 24/08/2021 21:54:34 |
3293 forum posts 112 photos | Thank you Duncan. I'm glad I was not the only one who'd not spotted the invisible brackets that make it work. I've never seen a clock like that previously. Anti-clockwise clocks yes. A clock with its otherwise plain dial given coloured segments to show pub opening times, yes. A clock with fancy single-digit sums though.... No. I like it! Edited By Nigel Graham 2 on 24/08/2021 21:55:11 |
noel shelley | 24/08/2021 22:22:42 |
2308 forum posts 33 photos | Gentlemen I'm glad it has generated some thought and comment, BUT I can claim no credit for it ! It was sent to me by an old school friend who paid less attention in maths than me, he also sent the WHAT IS IT I posted some weeks ago. I felt it was worth sharing. Ah well, Time Flies. Noel. |
duncan webster | 24/08/2021 23:45:05 |
5307 forum posts 83 photos | The 7 would be better as 9 - sqrt(9) + 9^0, which would be 9 - 3 + 1 = 7 The symbol for 0.99999......... in my young date was a dot above the 9, not a line Anyone know where I can get one, apart from Journeyman's South American Rainforest, which I must admit I didn't get |
Grindstone Cowboy | 25/08/2021 00:16:42 |
1160 forum posts 73 photos | Duncan - it's also a big river. I'm assuming we aren't allowed to mention the actual website? Rob |
Peter Greene | 25/08/2021 01:50:58 |
865 forum posts 12 photos | Posted by duncan webster on 24/08/2021 23:45:05:
The 7 would be better as 9 - sqrt(9) + 9^0, which would be 9 - 3 + 1 = 7
But unfortunately introduces the numeral " 0 " .... |
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