Wednesday, July 3, 2013

Fun math puzzles

Fun math puzzles


I try my best to provide you with fun math puzzles. Fun does not necessarily means easy. As a math major, anything that becomes challenging is fun for me. 

I cannot guarantee all the puzzles will be fun, but I can guarantee that some of the puzzles will be very challenging eventhough the skills that you need is basic math. Try to do the puzzles yourself before looking at the solution at the end of the page 

The puzzles on this page are warm ups. More complicated puzzles will be added on a regular basis

Let's get started with some fun math puzzles!

Puzzle #1:

Use four 5s and some of the symbols +, ×, −, and ÷ to give expressions for 0, 1, 2, and 5

Puzzle #2:

Use the two isosceles triangles below to make a star?

Isosceles-triangles-image
Puzzle #3:

It takes 1629 digits to number the pages of a book. How many pages does the book have?

Puzzle #4:

Use only 4 straight lines to cut a pizza into 11 pieces?

Puzzle #5:

would you rather work for 30 days and get paid 5 millions dollars, or be paid 1 cent the first day, 2 cents the second day, 4 cents the third day, and so on...?

Puzzle #6:

Place 10 dishes along the 4 edges of a table so that each edge has the same amount of dishes

Puzzle #7:

In a family with 4 siblings, John is older than Mary, Peter is younger than John, Mary is older than Peter, and Sarah is older than John. Who is the second oldest in the family? Who is the youngest?

Puzzle #1 solution:

5 − 5 + 5 − 5 = 0

5 − 5 + 5 ÷5 = 1

5 ÷5 + 5 ÷5 = 1 + 1 = 2

5 × (5 − 5) + 5 = 5

Puzzle #2 solution:

Star-made-with-2-triangles-image
Puzzle #3:

From page #1 to page # 9, there are 9 pages

From page #10 to page # 99, there are 90 pages. However, since each page number has 2 digits, there are 180 digits from page # 10 to page # 99 

From page #100 to page # 999, there are 900 pages. However, since each page number has 3 digits, there are 2700 digits from page # 100 to page # 999

Since there are 1629 digits, we know so far that number of pages is less than 900

Now, we need to find out how many digits there are for those pages greater than 99 or those pages with 3 digits

Since there are 189 digits for pages with less than 3 digits, we can subtract 189 from 1629 digits to find the number of pages with 3 digits

1629 − 189 = 1440

1440 represents the pages with 3 digits, so number of pages with 3 digits = 1440/3 = 480

Thus, total number of pages = 480 + 90 + 9 = 579 pages

Puzzle #4 solution:

11-pieces-pizza-image
Puzzle #5:

The trick is to find out how much money you make in 30 days if you get 1 cent the first day, 2 cents the second day, 4 cents the third day, and so on... Day 1: 1 cents

Day 2: 2 cents

Day 3: 4 cents

Day 4: 8 cents 

Day 5: 16 cents

Day 6: 32 cents

Day 7: 64 cents

Day 8: 128 cents

Day 9: 256 cents

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-------

-------

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Keep mutliplying by 2

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Day 30: 536,870,912 cents

536,870,912 cents/100 = 5,368,709.12 dollars and 5,368,709.12 is bigger than 5,000,000

Therefore, you are better off taking 1 cent the first day, 2 cents the second day, 4 cents the third day, and so on... until the 30th day

Puzzle #6:

If the blue rectangle represents the table and the red circles represent dishes, here is the solution

Dishes-around-a-table-image
Are you not tired yet with these fun math puzzles? Read on...

Puzzle #7:

In a family with 4 siblings, John is older than Mary, Peter is younger than John, Mary is older than Peter, and Sarah is older than John. Who is the second oldest in the family? Who is the youngest?

This puzzle. You solve it! Yes, the first person who solves this fun math puzzle with a detailed solution, will have his solution posted on this page with his name in parenthesis. As an added bonus, you can get my fractions ebook plus all bonuses with a donation of your choice

All other persons who solve this puzzle will not have their names listed, but they can get my fractions ebook and the bonuses with a donation of at least 10 dollars instead of paying the regular price of 29 dollars!

Here is the process to follow:

Send the solution using the form here

If you have the correct solution, I will contact you with further instructions. 

If you love these fun math puzzles, stay tune. This page will be updated with fun math puzzles on a regular basis!

NEW MOBILE PHONE PUZZLE AUTO SOLVER

Several minor bug fixes in this version
  • Tags on emailed puzzles are now encoded properly so spaces and funny characters all work ok.
  • Screen timeout is disabled when you are playing a puzzle.
  • A couple of weird display glitches are fixed - not sure when they appeared.
And, the big new feature:




You can now grab sudoku puzzles in real time! Just wait until the puzzle turns green and then touch the puzzle in the grey area - that will grab whatever puzzle was just recognised.

Top 10 TRICK QUESTIONS

Top 10 TRICK QUESTIONS

Top 10 TRICK QUESTIONS

TRICK QUESTIONS 1 : Hard Math Riddle
Difficulty ★★★★☆     Popularity ★★★★★


Take 9 from 6, 10 from 9, 50 from 40 and leave 6.

How Come ??

For Answers/Discussion : Click Here
==============================================

TRICK QUESTIONS 2 : Alexander Puzzle
Difficulty ★★★★☆     Popularity ★★★★★


Alexander is stranded on an island covered in forest.

One day, when the wind is blowing from the west, lightning strikes the west end of the island and sets fire to the forest. The fire is very violent, burning everything in its path, and without intervention the fire will burn the whole island, killing the man in the process.

There are cliffs around the island, so he cannot jump off.

How can the Alexander survive the fire? (There are no buckets or any other means to put out the fire)

For Answers/Discussion : Click Here
==============================================

TRICK QUESTIONS 3 : Trick Teaser Riddle
Difficulty ★★★☆☆     Popularity ★★★★☆


Jason decided to give his bike 3 coats of paint. Which coat would go on the first?

For Answers/Discussion : Click Here
==============================================

TRICK QUESTIONS 4 : Statement Riddle
Difficulty ★★★☆☆     Popularity ★★★★☆


'Ferari driver' easily beats the 'force indain driver' in a two care race.How did Indian newspapers truthfully report so to look as 'force indain drive' had outdone the 'ferari driver'
Think ??

For Answers/Discussion : Click Here
==============================================

TRICK QUESTIONS 5 : A Riddle
Difficulty ★☆☆☆☆     Popularity ★★★★☆


A bus driver was heading down a street in Delhi. He went right past a stop sign without stopping, he turned left where there was a 'no left turn' sign and he went the wrong way on a one-way street. Then he went on the left side of the road past a cop car. Still - he didn't break any traffic laws. Why not?

For Answers/Discussion : Click Here
==============================================

TRICK QUESTIONS 6 : Mothers Name Humour Puzzle
Difficulty ★☆☆☆☆     Popularity ★★★☆☆


A cat had three kittens: January,March and May. What was the mother's name. ?

For Answers/Discussion : Click Here
==============================================

TRICK QUESTIONS 7 : Number Trick Riddle
Difficulty ★★☆☆☆     Popularity ★★★☆☆


Sonal asked the class to see if they could find the sum of the first 50 odd numbers. As everyone settled down to their addition, Lavesh ran to her and said, 'The sum is 2,500.' Ms. Sonal thought, 'Lucky guess,' and gave him the task of finding the sum of the first 75 odd numbers. Within 20 seconds, Lavesh was back with the correct answer

How does Lavesh find the sum so quickly and what is the answer ??

For Answers/Discussion : Click Here
==============================================

TRICK QUESTIONS 8 : Trap Door puzzle
Difficulty ★★☆☆☆     Popularity ★★★☆☆


A man is trapped in a room. The room has only two possible exits: two doors. Through the first door there is a room constructed from magnifying glass. The blazing hot sun instantly fries anything or anyone that enters. Through the second door there is a fire-breathing dragon. How does the man escape?

For Answers/Discussion : Click Here
==============================================

TRICK QUESTIONS 9 : Maths Teaser
Difficulty ★★☆☆☆     Popularity ★★☆☆☆


Try to find out a multi-digit number that if multiplied by the number 9 or any of its multiplications products (18, 27, 36, 45,..) will result in the multiplication factor repeated (n) number of times

For Answers/Discussion : Click Here
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TRICK QUESTIONS 10 : sherlock puzzle
Difficulty ★★★☆☆     Popularity ★★☆☆☆


A wife and her husband were driving in their car on the highway. All of a sudden, they ran out of gas. So the husband said to the wife, 'Now, you stay here. I will go down the highway to the nearest gas station, and I will be about 1 hour. Just listen to the radio and read some books, and remember to lock all the windows and doors. I will leave the keys with you.' So, off the husband went, and the wife first locked ALL the windows and doors. Next, she turned on the radio, and this is what she heard on the news report:
'THERE IS A MURDERER ON THE LOOSE. HE WAS LAST SEEN ON THE HIGHWAY, WEARING ALL BLACK, ABOUT 5 FOOT 11 INCHES. PLEASE, BE AWARE AND CONTACT THE POLICE IMMEDIATELY.' The wife got very scared. She turned off the radio and double checked the locked doors. Then she saw the murderer, only a couple feet away from the car. An hour later, the husband returned to his car. Inside the car, his wife was DEAD, she had been murdered. All the windows were still locked, and the doors. No windows were broken, and the car was in PERFECT condition. No scratches or anything, it was the same way as when he left it. How did the murderer kill the wife?Yo dont need to be sherlock holmes to solve this ??

For Answers/Discussion : Click Here
==============================================

BONUS TRICK QUESTIONS : Engineer Physicist Mathematician puzzle
Difficulty ★★★★☆     Popularity ★★☆☆☆


A farmer challenges an engineer, a physicist, and a mathematician to fence off the largest amount of area using the least amount of fence.

The engineer made his fence in a circle and said it was the most efficient.

The physicist made a long line and said that the length was infinite. Then he said that fencing half of the Earth was the best.

The mathematician laughed at the others and with his design, beat the others. What did he do?

For Answers/Discussion : Click Here

Very Easy Maths Picture Puzzle

Very Easy Maths Picture Puzzle


Solve the picture puzzle by replacing the question mark with correct number ?

















For Solution : Click Here

Riddles For Kids 1 : Famous Riddle

Riddles For Kids

Top 10 Riddles For Kids

Difficulty ★★☆☆☆     Popularity ★★★★★

On my way to St. Ives I saw a man with 7 wives. Each wife had 7 sacks. Each sack had 7 cats. Each cat had 7 kittens. Kitten, cats, sacks, wives. How many were going to St. Ives?

For Answers/Discussion : Click Here

Fields: free puzzle app game for ipod touch, iphone, ipad Review


 
 Fields is an interesting puzzle app from Kevin Langdon.  The object is to fill the field with different colored flowers. The blue flowers always occupy 2 squares. The red flowers take up 5 squares.  You get the idea.

Kevin says: This game is so addicting, you may never leave the toilet again.

Now just a darn minute Kevin. You're going too far with that! Let it be known now and forever that I do not advocate anybody reading this blog, do play any games on the toilet. Just the thought makes me go EEEEwwwwwwww!

Let's talk gameplay.  This is quite good. I've played about half of the levels. More than once I've satisfied all of the regions, but have an empty square that must be filled.  These puzzles are well designed.

Fields could make the List of Best Puzzle Apps of 2013.  The awards will be published Dec 31.

https://itunes.apple.com/us/app/fields/id622406500?mt=8


Alexander Puzzle

Alexander Puzzle



Alexander is stranded on an island covered in forest.

One day, when the wind is blowing from the west, lightning strikes the west end of the island and sets fire to the forest. The fire is very violent, burning everything in its path, and without intervention the fire will burn the whole island, killing the man in the process.

There are cliffs around the island, so he cannot jump off.

How can the Alexander survive the fire? (There are no buckets or any other means to put out the fire)

For Solution: Click Here