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   Author  Topic: daughter's ages  (Read 3278 times)
klbarrus
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daughter's ages  
« on: Jul 25th, 2002, 5:03pm »
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The product of Dr. D's daughter's ages is 72, or 3*3*2*2*2. Trying out various combinations, we get these possibilities:
 
18, 2, 2; sum 22
9, 4, 2; sum 15
12, 3, 2; sum 17
6, 6, 2; sum 14
8, 3, 3; sum 14
6, 4, 3; sum 13
 
Since Dr. S can't figure out the ages from their sum, it must be either 6, 6, 2 or 8, 3, 3 as they both add to 14, and the rest are unique.  Dr. D said "his oldest" so this means his daughters are 8, 3, 3.
 
Of course, Dr. D might have been talking about the oldest twin of the 6 year old pair Wink
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Zy Baxos
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Re: daughter's ages  
« Reply #1 on: Jul 26th, 2002, 8:53pm »
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Addition to solution above:
 
You are ignoring a large number of possible age combo's:
 
1,1,72 - all right, not *that* possible
1,2,36 - "
1,3,24
1,4,18
1,6,12
1,8,9
 
Fortunately, all of these combinations have unique sums, so your answer still holds  Smiley
 
Regards,
Zy
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klbarrus
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Re: daughter's ages  
« Reply #2 on: Jul 27th, 2002, 11:33pm »
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Doh!  Thanks, I skipped all the factors of 1 as you said.
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