Mysterious Math

This problem can be solved by preschool children in five to ten minutes, by programmers in an hour and by people with higher education…well, check it yourself.

8809 = 6
7111 = 0
2172 = 0
6666 = 4
1111 = 0
3213 = 0
7662 = 2
9313 = 1
0000 = 4
2222 = 0
3333 = 0
5555 = 0
8193 = 3
8096 = 5
1012 = 1
7777 = 0
9999 = 4
7756 = 1
6855 = 3
9881 = 5
5531 = 0
2581 = ?

What is the missing number and why?

Two. The number is how many closed circles there are in the 4 digits. 0, 6 and 9 each have one, 8 has 2.

Posted in Brain Teasers

One Hundred With Six Identical Digits

How can you express the number 100 using the same digit six times?

99 + 99/99 = 100

Posted in Brain Teasers

Almost Catching Fire

People come and watch, from far away to see
Burning brightly, almost catching fire,
The colder it is the hotter I’ll be.
Then I die.

What am I?

Fall leaves changing colors. “Burning” with bright colors, when it’s cold outside the brighter the colors are.

Posted in Riddles
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I Move Quickly

Physicists have built devices to make me move quickly. My last eight letters can be commonly found in newspapers, magazines, and journals.

What am I?

Particles. Physicists use particle accelerators and newspapers, magazines and journals have articles.

Posted in Riddles
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Run Smoother Than Any Rhyme

What runs smoother than any rhyme, loves to fall but cannot climb?

Water

Posted in Riddles

Dumbstruck Beekeeper

Which word does not belong?

beekeeper, dumbbell, dumbstruck, untruthful

Dumbbell. All of the other words have only one of the vowels (a, e, i, o, u).

Posted in Brain Teasers

Paris to Roye

Hans made a meandering journey from Paris to Roye. On the first day, he went half of the distance. On the second day, he went one third of the remaining distance. On the third day he went three quarters of the remaining distance. The next day he traveled half of the remaining distance and was left with 5 kilometers to get to Roye. How far was the entire journey?

120 kilometers.

Hans’ trip went like this:

Day 1 – 60 km (60 km remaining)
Day 2 – 20 km (40 km remaining)
Day 3 – 30 km (10 km remaining)
Day 4 – 5 km (5 km remaining)
Day 5 – 5 km (arrives in Roye)

Posted in Brain Teasers

One In China

I am one in China,
Two in Indonesia,
Three in the Philippines,
None in Japan.

What am I?

The letter ‘i’.

Posted in Riddles
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I’ll Always Smile Back

If you drop me I’m sure to crack but give me a smile and I’ll always smile back

A mirror.

Posted in Riddles

Add An A But Sounds The Same

What word starts with the letter “I”, becomes another word by adding the letter “A” yet has the same pronunciation?

Isle, Aisle

Posted in Brain Teasers