Another simple math shortcut
May 13, 2022 10:01:39 #
MrBob wrote:
I prev. mentioned the Trachtenberg system of mathe... (show quote)
For you guys that know a lot about math and such, I was asked to figure out these sequences of numbers. One of them I still can't get. Can you help me? I'll give you all the examples I was given. The last one I couldn't figure out:
1. 8 _ 12 14
2. 23 26 30 35 _
3. 18 17 15 _ 8
4. _ 20 26 38 62
5. 5 _ 11 19 35
6* 70 _ _ 84
May 13, 2022 10:25:44 #
jeep_daddy wrote:
For you guys that know a lot about math and such, I was asked to figure out these sequences of numbers. One of them I still can't get. Can you help me? I'll give you all the examples I was given. The last one I couldn't figure out:
1. 8 _ 12 14
2. 23 26 30 35 _
3. 18 17 15 _ 8
4. _ 20 26 38 62
5. 5 _ 11 19 35
6* 70 _ _ 84
1. 8 _ 12 14
2. 23 26 30 35 _
3. 18 17 15 _ 8
4. _ 20 26 38 62
5. 5 _ 11 19 35
6* 70 _ _ 84
Looks like 76 (double up differences) - 70 +2 = 72, 72+4 = 76, 76+8 = 84.
May 14, 2022 11:19:16 #
Delderby wrote:
Looks like 76 (double up differences) - 70 +2 = 72, 72+4 = 76, 76+8 = 84.
Thank you. It was driving me crazy.
May 14, 2022 16:55:10 #
fosis
Loc: Pittsburgh, PA
Because 212-32F = 180 degrees from freeze to boil, and 100-0C = the same, then every 10C = 18F.
So just memorize the 10C conversions: 0=32, 10=50, 20=68, 30=86, 40=104, 50=122.
From that point on, it's easy to estimate, and then work out the exact: 25C=68+9 (half of 18)=77F for example.
By the way, -40C=-40F. Lots easier than trying to memorize a formula.
So just memorize the 10C conversions: 0=32, 10=50, 20=68, 30=86, 40=104, 50=122.
From that point on, it's easy to estimate, and then work out the exact: 25C=68+9 (half of 18)=77F for example.
By the way, -40C=-40F. Lots easier than trying to memorize a formula.
May 15, 2022 10:22:37 #
jeep_daddy wrote:
Thank you. It was driving me crazy.
The * on the last one DROVE me crazy... Typo or something to drive us crazy.. ?
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