School-Safe Puzzle Games

Up In Years

The day before yesterday, Lisa was 13. Next year she will be 16.

How is this possible?

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6 Comments to “Up In Years”


  1. barftud | Profile

    Today is January 1st
    Lisa’s birthday is December 31st.
    The day before yesterday she was 13.
    Yesterday she turned 14.
    At the end of this year she will be 15.
    At the end of next year she will be 16.


  2. bobg | Profile

    her birthday is dec 31, today is jan 1. On the last day of ‘next year’ she will turn 16.


    “last year” she was 13 until the 31st. this year she is 14 until the 31st. next year she will be 15, and on the 31st… 16!


  3. Sue | Profile

    Her birthday is Dec. 31st.


  4. markodiablo | Profile

    Today is 1st January and Lisa is 14. Her birthday is 31st December.


    Example for the year 2011…


    30/12/2011: Lisa is 13. (Day before yesterday)
    31/12/2011: Lisa is 14. (Yesterday)
    01/01/2012 (Today)
    31/01/2012: Lisa will be 15.
    31/01/2013: Lisa will be 16. (Next year)


  5. suineg | PUZZLE MASTER | Profile

    Cool puzzle, I think the answer is like this:


    Lisa was born on December 31


    Explanation:


    Suppose that Today is January 1 of 2012, the day before yesterday was December 30 of 2011, Lisa was 13 years old.
    The next day(yesterday) December 31 of 2011, its lisa 14 birthday
    the next day is January 1 of 2012. On December 31 of 2012 Lisa is 15 years old so next year Lisa will be 16.. just for one day of that year… trickyyyyyyyyyyyyyyyyyyyyyyyy jajaja but cool.


    However no math involved in my case.. just logic….anyway cool.


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