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In a certain laboratory, chemicals are identified by a color-coding sy
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12 Dec 2018, 02:24
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Question Stats:
62% (01:15) correct 38% (01:29) wrong based on 74 sessions
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In a certain laboratory, chemicals are identified by a color-coding system. There are 20 different chemicals. Each one is coded with either a single color or a unique two-color pair. If the order of colors in the pairs doesn't matter, what is the minimum number of different colors needed to code all 20 chemicals with either a single color or a unique pair of colors?
In a certain laboratory, chemicals are identified by a color-coding sy
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12 Dec 2018, 02:33
Bunuel wrote:
In a certain laboratory, chemicals are identified by a color-coding system. There are 20 different chemicals. Each one is coded with either a single color or a unique two-color pair. If the order of colors in the pairs doesn't matter, what is the minimum number of different colors needed to code all 20 chemicals with either a single color or a unique pair of colors?
A. 5 B. 6 C. 7 D. 20 E. 40
6c1 +6c2 : 21
IMO 6 should be correct.. IMO b
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Re: In a certain laboratory, chemicals are identified by a color-coding sy
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12 Dec 2018, 09:07
Let say there are 2 colors : A & B. All possible combination would be A , B , AB. If there are 3 : A, B & C. Combinations would be A , B , C , AB, AC , BC.
In a certain laboratory, chemicals are identified by a color-coding sy
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04 Jan 2019, 02:19
In a certain laboratory, chemicals are identified by a color-coding system. There are 20 different chemicals. Each one is coded with either a single color or a unique two-color pair. If the order of colors in the pairs doesn't matter, what is the minimum number of different colors needed to code all 20 chemicals with either a single color or a unique pair of colors?
CONSIDER ANSWER CHOICES
5 colours
A,B,C,D,E AB, AC, AD, AE BC, BD, BE CD, CE DE falls short of 20.
6 colours
all the above + a new colour F F, FA, FB, FC,FD, FE totals 21.
B is the correct option.
gmatclubot
In a certain laboratory, chemicals are identified by a color-coding sy &nbs
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04 Jan 2019, 02:19
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62% (01:15) correct 
