Card Hypothesis

FACT: Each card has a number on one side and a letter on the other.
HYPOTHESIS: Every card that has a vowel on one side has an even number on its opposite side.
THE TEST: Which card or cards must you turn over in order to test the Hypothesis?


Type your answer in the Reply field below and Save.
The 15 possible answers are:

All four cards: A B C D
Three cards: A B C / A B D / A C D / B C D
Just two cards: A and B / A and C / A and D / B and C / B and D / C and D
Just one card: Card A only / Card B only / Card C only / Card D only

About davidbdale

Inventor of and sole practitioner of 299-word Very Short Novels.
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31 Responses to Card Hypothesis

  1. oaktree1234 says:

    all four

  2. bigblue821 says:


  3. runnerd4 says:

    ABCD to be sure that it is correct for all cards

  4. rowanstudent24 says:

    You have to turn over 2 cards. Card A and Card C because card A has a vowel on it and Card C has an even number on it.

  5. jeffbezos123 says:

    In order the hypothesis you would need to turn over all for cards. This is because you want to see all of your possible outcomes. This is because when you are testing a theory you want to try and prove it wrong or prove it right

  6. clementine102 says:

    I think you just have to flip card C because the hypothesis is only asking for a card that has an even number. The card that defiantly has an even number is card C. The hypothesis will be correct is card C has a vowel on the other side.

  7. thecommoncase says:

    In order to test the hypothesis you must turn over all four cards because in order to prove the vowels and even numbers are on the same card and the consonants go with the odd numbers.

  8. shadowswife says:

    Turn over both cards A and C.

  9. cfriery says:

    You must turn over two cards, which are cards A and C because our hypothesis is only testing for vowels and even numbers.

  10. Nimadhury says:

    I believe just flipping C will be enough to test the hypothesis. This is because we’re only concerned about vowel/even number cards.

  11. cucumberlemonadee says:

    All four cards

  12. hailthegreat8 says:

    A and C

  13. tcarter101 says:

    A B C D

  14. pardonmyfrench13 says:

    Turn over both A and C.

  15. gooferious says:

    All 4 cards

  16. comicdub says:

    Just two cards: A and C

  17. dayzur says:

    All four cards

  18. pizzaplanet323 says:

    A B C D

  19. l8tersk8ter says:

    All four – ABCD, if you flip over A and C and they happen to have a vowel and even number, that doesn’t mean the other cards can’t have a mismatch odd number and vowel or even number and consonant

  20. gabythefujoshi18 says:

    Turn over card A and C, because card A is a vowel and card C is an even number

  21. rowanstudent says:

    I would say turn over the one vowel because that is what ur hypothesis states.

  22. mhmokaysure says:

    A and C. By turning over both A and C you can see if both vowels have even numbers, seeing as the hypothesis is testing vowels against even numbers.

  23. ivellisemorales says:

    Flip c and b

  24. corinnebuck1219 says:

    turn over card A and card C

  25. bluntwriting88 says:

    We only need to turn over card A and Card D to test the hypothesis. This is because a Vowel will have an even number on its opposite side if-and-only-if the hypothesis is true. If we turn over the 3, this will either verify or invalidate our hypothesis. This is also the case if we Turn over the E card.

  26. mesrurerowan says:

    Turn over all four

  27. wafflesrgud22 says:

    turn a and c

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