Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How old are my daughters?

  1. Sep 1, 2004 #1
    The host of the party was wonder what to do to make the party a little more interesting. So he though for a second, and he yelled out,"If anyone can solve this brain teaser, I will give you $20." This got the crowd's attention.
    The host then thought for a minute, and he said,"If you can figure out the age of my 3 daughters, and my appartment number, from the clues I give you, you win!" He then stated the following clues:

    1)The product of multiplying my daughter's ages together will give you the number 72.

    2)The sum of my daughter's ages together will give you my appartment number.

    A man in the crowd thought for a second, and had an idea. So he ran out and looked at the host's appartment number. He came running back in screaming,"Not enough information. Not enough information!"

    The host realized his mistake. He then gave the next clue:

    3)My oldest daughter LOVES strawberry pudding.

    From the information about, figure out the ages of the host's daughters and the appartment number of the host. You must prove why you came up with your answer.

    My clue:
    There may be twins.
    Whole numbers only.

    Paden Roder

    Once again, I may have, by accident, left little details out. If you are having trouble, just ask.
  2. jcsd
  3. Sep 1, 2004 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    My answer : <select to see>Their ages are 8,3,3 (other possibility with sum = 14 is 2,6,6 is ruled out by the eldest daughter clause). The only squares that divide 72 are 4, 9, 36 resulting in the possibilities : (2,2,18), (3,3,8) and (6,6,2). Fortunately for me, the last two of these sets have the same sum, and one of them has a unique largest element.

    I think the host didn't intend the guests to also figure out the house number. If that were so, the dude that ran outside to check was breaking the rules - or at least violating the spirit of the question. Besides, it would be unlikely that all the guests made it to the correct house without knowing the house number.
    Last edited: Sep 1, 2004
  4. Sep 2, 2004 #3


    User Avatar
    Science Advisor
    Homework Helper

    Gokul, what makes you think all of the guests were ethical. Personally, knowing the oldest daughter loved strawberry pudding was the clue I needed.

    I quickly pulled out the assortment of pudding packs I always carry around with me for emergencies, selected one of the strawberry flavored ones, and simply told the oldest daughter I'd give her a pack of strawberry pudding if she told me how old she and her sisters were.

    Select to see her answer:

    "No way. I'd never sell out my sisters. Make it three pudding packs and you've got a deal."

    (Sorry for the delay - I had to go get more pudding packs)
    I eventually found out the oldest daughter was 8 and her twin sisters were 3.

  5. Sep 2, 2004 #4
    Once again, Gokul with a point. Nice story BobG. hehe.

    Paden Roder
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook