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# A puzzle

Ranch Hand
Posts: 189
From Brainjuice

Alvin and Buzz are nerds and like doing nerdy things. So Alvin called Buzz one day...

"Buzz, I've finished tracing my family tree back from the year 500 AD, and I found one quite special guy".

"Well, he was x years old in the year x^2 (x squared) and he had a son who was y years old in the year y^3 (y cubed)".

Buzz looked perplexed "Sorry Alvin, but I can't solve for x or y".

"Well, he was your age when his son was born." said Alvin.

"You're right" said Buzz "He was a special old guy! But I still can't solve for x or y".
How old was the old guy when his son was born?

Sheriff
Posts: 6450
Moved to Programming Diversions.

Ranch Hand
Posts: 1923
I got multiple solutions, depending on what you think which is 'really old'.
Today, ages of over 130 years where reported.
For 1320 this would be a nearly impossible age, but do we have a proof?

0011000100110011001100000010000000110001001100100011000000100000001100010011001000110000
0011011100110110001000000011011100110000001000000011011000110000001000000011011000110000

blacksmith
Posts: 1332
2
Try winnowing your answers down with the "but I still can't solve for x or y" constraint? If Buzz is 130, he can uniquely determine both x and y, I think.

Stefan Wagner
Ranch Hand
Posts: 1923
Ah - I thought Buzz is a fool.
Not a perfect logican...

So I will look at my approach again.

Greenhorn
Posts: 6
son at 11----->year was 1331
father at 36--->year was 1296
father was 60 years when got son...

Ranch Hand
Posts: 128
OR ....
son at 12----->year was 1728 son born in 1716
father at 41--->year was 1681 dad born in 1640
father was 76 years when his son was born 0076

Stefan Wagner
Ranch Hand
Posts: 1923

Two possibilities, so Buzz doesn't know x and y.

Sonny Pondrom
Ranch Hand
Posts: 128
OR...
120 age of F at birth Age F: 0 year: 0 Age s: 5 year: 125
120 age of F at birth Age F: 10 year: 100 Age s: 6 year: 216

:roll: