• The Three Children

    Tom\’s mother has three children. One is named April, one is named May. What is the third one named?

    Spoiler

    Tom 🙂

  • The Heavier One

    If you had 1000 kilograms of feathers and 1000 kilograms of stones which would be heavier?

    Spoiler

    Neither. They both weigh 1000 kilograms.

  • The Owner with the Canaries

    I am the owner of a pet store. If I put in one canary per cage, I have one bird too many. If I put in two canaries per cage, I have one cage too many.

    How many cages and canaries do I have?

    Spoiler

    Four canaries and three cages.

    If you put one canary in each cage, you have an extra bird without a cage. However, if you put two canaries in each cage then you have two canaries in the first cage, two canaries in the second cage and an extra cage.

  • The Cook

    You are a cook in a remote area with no clocks or other way of keeping time other than a four-minute and a seven-minute hourglass. On the stove is a pot of boiling water. Jill asks you for a nine-minute egg, and you know she is a perfectionist and can tell if you undercook or overcook the egg by even a few seconds. How can you cook the egg for exactly 9 minutes?

    Spoiler

    1. Flip both hourglasses over and drop the egg into the water.
    2. When the 4-minute timer runs out, flip it over (4 minutes elapsed, 3 remaining on the 7-minute timer).
    3. When the 7-minute timer runs out, flip it over. (7 minutes elapsed, 1 remaining in the 4-minute timer)
    4. When the 4-minute timer runs out, flip the 7-minute timer over. (8 minutes elapsed. 6 minutes remained in the 7-minute timer, but flipping it over leaves one minute\’s worth of sand on top. When it runs out exactly nine minutes will have elapsed.

  • The Strange 2 Seconds

    Noemie puts her coffee into the microwave, as she does every morning, for exactly 2 minutes. When the microwave goes off, she opens the door, but then closes the door again and sets the microwave for 2 more seconds. What good would 2 more seconds be?

    Spoiler

    To rotate the handle on the mug so she can comfortably remove it.