Hi there :)
I come up with some interesting math puzzles and riddles. A word of advice before you start solving these puzzles. If you really get stuck, don't give up or you'll spoil the fun. Put the sticky puzzle aside, or you can try to solve an easier puzzle similar to the sticky one. Or just guess trial answers just to see if they make sense. Who knows, you might be lucky and hit on the right answer. Of course, fluke answers will not be satisfying than working out the puzzle logically.
You need not worry about the correct answer. You will find answers right below the puzzle. But i suggest you to look up the answer as the last resort. This may give you the clue you need without giving the game away. As you will see, I have written very complete answers to the harder puzzles or to those needing several steps to solve. But trust me most of the puzzles call for straightforward arithmetic or simple reasoning. And some of them can just be solved by trial and error method.
I know you just can't wait anymore. Let's begin.
Puzzle 1:
Find 2/3 of 3/4 of 12. Also find 2/3 of 3/4 of 20. Can you discover the trick to doing this quickly?
Answer
For 12, {2/3 of (3/4 of 12) } = {2/3 of 9} = 6
For 20, {2/3 of (3/4 of 20) } = {2/3 of 20} = 10
Trick: The answer will be always half the given number.
Puzzle 2:
Divide the clock face below by drawing only two lines such that the numbers in the each section add up to the same sum.
Answer
Puzzle 3:
Count the number of blocks in each arrangement. Assume that visible blocks rest on identically shaped hidden blocks, and that every arrangement is solid.
Answer
Puzzle 4:
Divide the hexagon below so that each dot is in its own rectangular box. All the boxes must be same size, and there should not be any spaces between the boxes.
Answer
Puzzle 5:
Take a card. Using a ruler, draw ten lines (for convenient) on the card, make sure that each line is exactly the same length. Next, use the ruler to trace a diagonal line from a top corner of the card to a bottom corner. Cut the card in half along this line (as shown in the below figure).
Now slide one half of the card along the other half just far enough so that the ten lines turn into nine. Where did the tenth line go?
Answer
Actually, most of you would have got the answer as the tenth line was "just absorbed" into the nine lines and then measure one of the original ten lines, you will find that each of the nine lines is slightly longer than each of the ten lines.
Puzzle 6:
There was a race between six tree choppers to see who could chop down a tree first. Study the drawing below. Can you tell which chopper won first place in the contest? Which choppers won second, third, fourth, and fifth places? And finally, who came in last?
Answer
First place was E, Second was C, Third was A, Fourth was B, fifth was F and last place was D.
Puzzle 7:
Of the six glasses below, three are filled with Strawberry juice. By moving only one glass in the top row, make the top row resemble the bottom row.
Answer
A general sense solution is in order here: pour the strawberry juice in glass #5 into glass #2 and return empty glass #5 to its original position :)
Puzzle 8:
If five men can do the work in five minutes. How long will it take for fifty men to do the same work?
Answer
Fifty minutes? No.
Five minutes. Each men takes five minutes to do the work no matter how many are doing the same work. The time element remains constant and does not influence the outcome of this problem.
Puzzle 9:
With your bow and arrow, shoot out the following scores on the target using the smallest number of arrows:
A. Shoot a score of 25.
B. Shoot a score of 19.
C. Shoot a score of 47.
Answer
A. 16 , 8 , 1 (three arrows)
B. 16, 2, 1 (three arrows) and
C. 32, 8, 4, 2, 1 (five arrows).
Note: You can form any whole number up to 63 on this target. Each number is a power of 2, which means that you can create any other whole number by combining numbers.
Puzzle 10:
An important receipt was badly burnt in a fire. Can you re-construct the missing digits so that the equation works?
Answer
1 4 2 5
+ 5 2 4 1
6 6 6 6
- 2 3 7 4
4 2 9 2
Puzzle 11:
On opposite sides of a street, there are 45 streetlights, each one at a distance of 30 yards from the other.
The streetlights on one side are arranged so that each lamp fills a gap between two other streetlights on
the opposite side. How long is the street?
Answer
It's 660 yards.
There are 23 lamps on one side and 22 on the other side. There are 22 gaps between 23 lamps.
Therefore, the street is 22 times 30 yards long, or 660 yards.
Puzzle 12:
Four gentlemen and their wives wanted to cross the river in a boat that held no more than two people at a time. The conditions were: A gentleman could not leave his wife on the bank without him unless she was either alone or only in the company of one or more women, and that someone must bring the boat back. How did they do it?
Answer
Here's a code for the four gentlemen and their wives.
Ml and Wl for the first man and first wife,
M2 and W2 for the second man and second wife,
M3 and W3 for the third, and M4 and W4 for the fourth.
1st crossing: Ml and Wl cross; Ml returns.
2nd crossing: M2 and W2 cross; M2 returns.
3rd crossing: M l and M2 cross; M2 and W2 return.
4th crossing: W2 and W3 cross; M l returns.
5th crossing: M l and M2 cross; W3 returns.
6th crossing: M3 and M4 cross; M3 returns.
7th crossing: M3 and W3 cross; M4 returns.
8th crossing: M4 and W4 cross.
Puzzle 13:
Solve the following percent problems and write the correct answers in the spaces on the puzzle. Decimal points, percent signs, and slash signs all take up a single space and there are no zeros before decimals less than one.
Across
| 1. Write 89% as a decimal. | 11. Write 5⁄2 as a percent. |
| 3. Write 1⁄2 as a decimal. | 12. Write 6% as a decimal. |
| 5. Write 3⁄4 as a decimal. | 14. Write 30% as a decimal. |
| 8. Write 50% as a decimal. | 15. Write 13⁄20 as a decimal. |
| 9. Write 1⁄5 as a decimal. | 17. Write 150% as a decimal. |
Down
| 2. Write .81 as a percent. | 10. Write .4 as a fraction. |
| 4. Write 11⁄2 as a decimal. | 11. Write .02 as a percent. |
| 5. Write 1⁄20 as a decimal. | 12. Write 30.5% as a decimal. |
| 6. Write .05 as a percent. | 13. Write 650% as a decimal. |
| 7. Write 1 as a percent. | 16. Write 1⁄20 as a percent. |
Answer
I hope you liked the puzzles. Stay connected many more are coming :)
0 Comments