Saw this one on a test. Think outside the box.
9*2=13
5*3=11
4*9=21
9*4=17
What does 7*8 equal?
note: the * does not indicate multiplication. It indicates some sort of action or actions.
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10 replies to this topic
#1
flamebirde
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Posted 24 October 2012 - 04:10 AM
Mafiosos and mafiosas of the world, unite! And then kill each other in a particularly tricky move that everyone suspects but never anticipates.
stand back. I'm going to apply logic.
#2
ohiocpa1
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Posted 24 October 2012 - 04:32 AM
double the smaller number, add to the larger
7*8 = (2x7) + 8 = 22
7*8 = (2x7) + 8 = 22
#3
Caliban27
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Posted 24 October 2012 - 08:12 AM
That won't work, 'cause 4*9 would be 17 not 21.double the smaller number, add to the larger
7*8 = (2x7) + 8 = 22
A variation to that theme which would work is: if second number is smaller, then [first number] + twice [second number], else, [first number] + twice second number] - 1. That is quite inelegant, and does not solve for instance of both numbers the same. Back to thinking further outside cube.
Edited by Caliban27, 24 October 2012 - 08:12 AM.
#4
Emil
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Posted 24 October 2012 - 09:22 AM
Spoiler for Am I on the right track?
Edited by Emil, 24 October 2012 - 09:23 AM.
#5
CaptainEd
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Posted 24 October 2012 - 03:30 PM
Spoiler for Not much more elegant, but fits the data we have
#6
vinay.singh84
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Posted 24 October 2012 - 05:17 PM
Spoiler for Not much more elegant, but fits the data we have
floor(x + 1) is more easily written as ceil(x)
#7
Pickett
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Posted 24 October 2012 - 05:41 PM
He's not flooring x+1...he's flooring (x+1) / 2...just FYI...floor(x + 1) is more easily written as ceil(x)
#8
CaptainEd
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Posted 24 October 2012 - 05:48 PM
Spoiler for Thanks to Vinay and Pickett, slightly more compact...
#9
flamebirde
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Posted 25 October 2012 - 12:28 AM
oops, sorry... screwed up on 4*9. it should equal 22.
REVISED QUESTION:
9*2=13
5*3=11
4*9=22
9*4=17
What does 7*8 equal?
note: the * does not indicate multiplication. It indicates some sort of action or actions.
With this in mind, Emil is very close to the answer but not quite.
REVISED QUESTION:
9*2=13
5*3=11
4*9=22
9*4=17
What does 7*8 equal?
note: the * does not indicate multiplication. It indicates some sort of action or actions.
With this in mind, Emil is very close to the answer but not quite.
Mafiosos and mafiosas of the world, unite! And then kill each other in a particularly tricky move that everyone suspects but never anticipates.
stand back. I'm going to apply logic.
#10
Rob_Gandy
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Posted 25 October 2012 - 01:03 AM
Spoiler for Hm..
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