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        riddles >> easy >> How old are you and how old am I?
        
(Message started by: jamaamtulivu on Jul 15^th, 2005, 11:16am)

Title: How old are you and how old am I?
Post by jamaamtulivu on Jul 15^th, 2005, 11:16am

Ive spoken to three people this morning, if you multiply their ages by mine you get 2450. One of the people I talked to recently celebrated a very important birthday, I celebrated the same birthday five years ago. If you add the ages of the people I talked to, the result will be double your age. How old are you and how old am I?
Clue: Both ages are over 25yrs

Title: Re: How old are you and how old am I?
Post by Leonid Broukhis on Jul 15^th, 2005, 2:11pm

What does "multiply their ages by mine" mean?

Is it (age1 * age2 * age3 * my_age) or ((age1 + age2 + age3) * my_age) ?

Title: Re: How old are you and how old am I?
Post by jamaamtulivu on Jul 15^th, 2005, 11:44pm

I guess you have to try whichever option you feel is right to get the answer. Thats how the original riddle appears.

Title: Re: How old are you and how old am I?
Post by THUDandBLUNDER on Jul 16^th, 2005, 7:21am

on 07/15/05 at 23:44:42, jamaamtulivu wrote:

I guess you have to try whichever option you feel is right to get the answer.

Ah, so that's why it is in Hard. ::)

on 07/15/05 at 11:16:08, jamaamtulivu wrote:

How old are you and how old am I?
Clue: Both ages are over 25yrs

Let 'mine' = m
Let 'yours' = y

Let a₁a₂a₃ * m = 2450 = 2 * 5² * 7²
m > 25 => m = 35 or 49
So {a₁,a₂,a₃} = {2,5,7} or {2,5,5}
"One of the people I talked to recently celebrated a very important birthday, I celebrated the same birthday five years ago. "
But m - 5 = 30 or 44
Obviously this cannot be true.
Contradiction.

So it must be (a₁ + a₂ + a₃) * m = 2450
Hence a₁ + a₂ + a₃ = 50 or 70 = 2y
y > 25 => y = 35

Hence my age = your age = 35

Title: Re: How old are you and how old am I?
Post by jamaamtulivu on Jul 17^th, 2005, 5:47am

The answer is not 35! Please keep on trying...

Title: Re: How old are you and how old am I?
Post by THUDandBLUNDER on Jul 17^th, 2005, 6:50am

on 07/17/05 at 05:47:45, jamaamtulivu wrote:

The answer is not 35! Please keep on trying...

...and you should keep on trying to post well-defined puzzles.
For example, are the two ages (mine and yours) required to be positive integers? Anyway, never mind the so-called answer; in what way does m = y = 35 and a₁ = 30 and a₂ + a₃ = 40 fail to satisfy your loosely-worded constraints?

After all,
m = y = 35 > 25
a₁ = m - 5
a₁ + a₂ + a₃ = 70
giving
(a₁ + a₂ + a₃)*m 2450
and
a₁ + a₂ + a₃ = 2y

Title: Re: How old are you and how old am I?
Post by jamaamtulivu on Jul 17^th, 2005, 10:11pm

Now...here is the full story and you thought it could get easier! There are two friends, Michelle and Andrea. Michelle's father is interested in Andrea and since he's older than Andrea, he tells Andrea that he's talked to three people this morning and if he multiplies their ages by his own the answer is 2450. One of the three people that he's talked to recently celebrated a very important birthday, he celebrated the same birthday 5years ago. He then tells Andrea that if he adds the three ages(of the people that he talked to) together the result will be double Andrea's age. Andrea is then able to calculate Michelle Father's Age while ofcourse knowing her own age. And now back to the riddle, how old is Michelle's father and Andrea?? And its not 35years!
Note: Both ages are of course positive integers.

Title: Re: How old are you and how old am I?
Post by fatball on Jul 25^th, 2005, 7:57am

Jamaamtulivu, since you are so confident about your riddle and yourself, I hope you did not commit any silly mistake in your riddle; however, I noticed that the second (and original) version you quoted is significantly different from the one you INVENTED and tried to simplify (but indeed complicate due to your own 'hint', i.e., the statement that both are over 25 years). I believe the only valid hint in this case is that both are NOT LESS THAN 25 years old in order to find a solution other than 35 and 35. Otherwise TB's solution is the only feasible solution given your 'hint'.

TB, I think the solution in Jamaamtulivu's head is that I am 49 (the father) and you are 25 (young lady), which makes sense if the two people are at two different generation, but our confident Jamaamtulivu failed to mention this fact in his own version of the riddle.