Each month, a new set of puzzles will be posted. Come back next month for the solutions and a new set of puzzles, or subscribe to have them sent directly to you.
MIND-Xpanders
- What is the number of degrees that the hour hand of a clock moves through between noon and 4:30 in the afternoon of the same day?
- Raeanne takes 20 minutes to jog around the race track course once, and 25 minutes to jog around a second time. What is her average speed in miles per hour for the whole jog if the course is 3 miles long?
- Two equal circles are cut out of a rectangular paper card of dimensions 8 cm by 16 cm. The circles have a maximum radius possible. What is the area of the paper remaining (shaded area) after the circles have been cut out as shown? (note: use π = 3.14)
Feedback
There are more than one way of doing these puzzles and may well be more than one answer. Please let me and others know what alternatives you find by commenting below. We also welcome general comments on the subject and any feedback you'd like to give.
If you have a question that needs a response from me or you would like to contact me privately, please use the contact form.
Get more puzzles!
If you've enjoyed doing the puzzles, consider ordering the books;
- Book One - 150+ of the best puzzles
- Book Two - 200+ with new originals and more of your favourites
Both in a handy pocket sized format. Click here for full details.
Last month's solutions
MATCHSTICK Challenge
Move only two of the matchsticks in diagram a) to turn the chair upside down.
Move only three of the matchsticks in diagram b) to create three equal squares.
All match sticks must be used.
Solutions:
MIND-Xpander (Circular Logic Challenge – Level 2)
You have 100 sticks standing upright in a circle (#1 to #100). Starting with stick #1, knock over the next stick (#2) in the circle. Then continue by knocking over every second stick (next is #4). Keep going around and around the circle until one stick remains standing. What number is the last stick standing?
What if you start half way around with stick #50 and continue around and around in same manner as above?
Solutions:
