# Finding secret number puzzle

Find a secret 10-digit number where the first digit is equal to number of zeros in the number, the second digit is equal to number of one in the number and so on, until the tenth digit which is equal to number of nines in the number.

**Answer- 6210001000**

**Explanation-**

Here is how I did it:

The first digit = frequency of occurrence of the number 0

The Second digit = frequency of occurrence of the number 1(this was the tricky part)

.

.

.

The 10th digit = frequency of occurrence of the number 9.

I have written the digits in columns and started out with the number 0000000000 in step 1.

**Step2**: Since we have 10 zeroes, it means that the first digit of our number must be 10. But since 10 is not a digit, I will use 9. This also makes the number of zeroes in my number as 9.

**Step3**: Since the first digit is 9, it means that the 10th digit must be one (because it gives the frequency of 9 in our number.

**Step4:** But now we only have 8 zeroes in our number. So I will make the first digit as 8 and the 9th digit as 1.

**Step5:**Since my number has the digit 1, my second digit must be 1. But now I am left with only 7 zeroes.

**Step6:** I will make my first digit 7 (because after step5 I am left with only 7 zeroes). And since Step5 had 2 ones, I will make my second digit 2. OMG… but this now makes number of 1’s in my number 1 and not 2. This means that I f the digit 1 is there in any place other than second digit, I am bound to come across this problem. So let me keep the second digit 2 and try to introduce another ‘1’ in some place.

**Step7: **Since I have to introduce one more 1, it means that the number of zeroes in my number have come down to 6. So my first digit will be six, my second digit will be 2 and my 6th digit will be 1.

**Step8:** The digit ‘1’ seems to be in the wrong place in Step 6. There is no ‘7’ but there is a 2. Let me just shift this ‘1’ from digit 8 to digit 3.

And there it is…**6210001000**

### Your Answer

## More puzzles to try-

### What is the logic behind these ?

3 + 3 = 3 5 + 4 = 4 1 + 0 = 3 2 + 3 = 4 ...Read More »### Which letter replaces the question mark

Which letter replaces the question markRead More »### 2 Eggs and 100 floor Google Classic question

There is a building of 100 floors -If an egg drops from the Nth floor or above it will break. ...Read More »### Five greedy pirates and gold coin distribution Puzzle

Five puzzleFry ship’s pirates have obtained 100 gold coins and have to divide up the loot. The pirates are all ...Read More »### Defective stack of coins puzzle

There are 10 stacks of 10 coins each. Each coin weights 10 gms. However, one stack of coins is defective ...Read More »### Dr. Willam and surgical gloves puzzle

Dr.Willam wants to operate for three different persons who were wounded. But he had only two surgical gloves. There is ...Read More »### Which clock works best?

Which clock works best? The one that loses a minute a day or the one that doesn’t work at all?Read More »### To which one will the needle touch 1 OR 2

In the gear arrangement, To which one will the needle touch, 1 OR 2Read More »### How did he know?

A man leaves his house in the morning to go to office and kisses his wife. In the evening on ...Read More »### Which room is safest puzzle

A murderer is condemned to death. He has to choose between three rooms. The first is full of raging fires, ...Read More »### Crossing the Bridge Puzzle (Bridge and torch problem)

A bridge will collapse in 17 minutes. 4 people want to cross it before it will collapse. It is a ...Read More »### Probability of having boy

In a country where everyone wants a boy, each family continues having babies till they have a boy. After some ...Read More »### Magical flowers!!

A devotee goes to three temples, temple1, temple2 and temple3 one after the other. In front of each temple, there ...Read More »### How many times a day do all three hands of analog watch overlaps?

There is a perfectly accurate analog watch with hour, minute, and second hands. How many times a day do all three ...Read More »### Tuesday, Thursday what are other two days staring with T?

Four days are there which start with the letter ‘T‘. I can remember only two of them as “Tuesday , Thursday”. ...Read More »### How could only 3 apples left

Two fathers took their sons to a fruit stall. Each man and son bought an apple, But when they returned ...Read More »### How Many Eggs ?

A farmer is taking her eggs to the market in a cart, but she hits a pothole, which knocks over ...Read More »### Minimum number of persons needed to cross a Desert

In the middle of the confounded desert, there is the lost city of “Ash”. To reach it, you will have ...Read More »### Lateral thinking sequence Puzzle

Solve this logic sequence puzzle by the correct digit- 8080 = 6 1357 = 0 2022 = 1 1999 = ...Read More »### Pizza Cost Math Brain Teaser

Jasmine, Thibault, and Noah were having a night out and decided to order a pizza for $10. It turned out ...Read More »