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ICAS problem (1 Viewer)

mathpie

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Icas results are out online, and only 20% answered this problem, which seems relatively easy at first, correctly:

Mary had 3 identical cubes. each cube has one pink face and one yellow face. the rest of the faces were blue. she joined the cubes as shown to form a solid (3 cubes connected in a line). what is the probability that the faces on the Bottom of the solid have 3 different colours.

the first thing I thought was 3! x 1/6 x 1/6 x 4/6 = 1/9
3! for the no. of ways the colours can be arranged
1/6 for the probability that yellow and pink are at the bottom
4/6 for the probability that blue is at the bottom.

but the correct answer is 7/48 ?? an explanation would be greatly appreciated.
 

peter ringout

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Yep 1/9 seems right.Could you post a png of the question and also the paper and the year thanks.
 

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