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.
Puzzle One
A magic rectangular cloth always shrinks its length to 1/2 and width to 1/3 whenever its owner wishes something. After three such wishes, its surface is now 4cm2.
What was the original length if the original width was 9cm?
Puzzle Two
A bag containing coins of 1 dollar, 50 cents and 25 cents in the ratio 3 : 5 : 7. The total amount is $1,856.00. Find the number of coins for each denomination.
Puzzle Three
Below is an special safe’s keypad . To open, you must press the keys in the correct sequencer until the last key marked ‘OPEN’. The number on each key tells you how many keys that you must move and the letter tells you in which direction to move (U = up, D = down, L = left and R = right). Which key is the first key in the sequence that you must press to open the safe?
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Last month's solutions
Puzzle one
In the following equations, the value of each of the playing cards (clubs, diamonds, spades, and hearts) will make each equation true. The value of the cards can only be 1 to 10. Find their values.
Solution:
Puzzle two
In the following numeric series: 8, 20, 64, 260, ?. What would be the next number (5th) in the series?
Solution:
On the second term, multiply the first term by 3 and then add 4 to the product. All follow on terms, multiple the previous term by one more then the previous term and continue to add 4.
1st term: 8
2nd term: (8*2)+4 = 20
3rd term: (20*3)+4 = 64
4th term: (64*4)+4 = 260
5th term: (260*5)+4 = 1304
Puzzle three
The total weight of a tin and the cookies it contains is 2 pounds. After ¾ of the cookies are eaten, the tin and the remaining cookies weigh 0.8 pounds. What is the weight of the tin in pounds?
Solution:
Let the weight of the empty tin = w, and
One quarter of the biscuits weigh ¼ (2 – w)
Then, one quarter of the biscuits + the tin = 0.8 pound = w + (2 – w)/4 and multiplying both sides by 4,
Therefore,: 3.2 = 4w + (2 – w); 3w = 3.2 – 2 = 1.2; w = 0.4 pounds