Question 117455
The answer to this problem is found by first determining how many eggs are hidden. The number
of eggs that are hidden is the total of 12 and 16 which is a total of 28 eggs. Then you  have
12 chances of finding a yellow egg as your first egg because there are 12 yellow eggs that are 
hidden. So the probability of finding a yellow egg first is the ratio of the number of 
yellow eggs to the total number of eggs. In fractional form this is:
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{{{12/28}}}
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and since 4 is a factor of both the numerator and the denominator of this fraction you can reduce
the fraction by dividing the numerator and denominator by 4 to get:
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{{{3/7}}}
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So D is the correct answer.
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You can immediately eliminate answers B and C because the correct answer must have 28 
as the original denominator. Therefore, the denominator of the correct answer must be
a factor of 28 which are 28, 14, 7, 4, 2 and 1. Therefore, the correct answer must have
one of these numbers as its denominator. Answers A and D do, but answers B and C do not. 
Therefore, they can be eliminated.
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Hope this helps you to understand the problem a little better.
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