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As head of Brilliant's cybersecurity, you need to know how many different passwords can be created by rearranging the digits 1, 2, 3, 4, 5, and 6. Can you count them all?

Permutations: Level 1 Challenges


There are 3 flights from California to France, and 2 flights from France to India. Sanjeet wants to fly from California to France and then to India.

How many choices does he have for his flight plan?

You have 3 different colored bottles, each with a distinct cap. In how many ways can these caps be put on the bottles such that none of the caps are on the correct bottle?

Details and Assumptions:

  • All the caps should be on the bottles.

After she'd almost finished planning the parade layout, Alice's boss let her know that he was adding some more participants to the parade. "There's no way I can finish this in time now!" Alice said. "There must be more than a billion possibilities!"

What is the minimum number of participants in the parade that will give more than a billion possible orderings?

How many integers are there from 1 through 999 that have distinct digits?

If you write all the whole numbers upto 100000, the number of times you write the digit '1' is A and the number of times you write the digit '2' is B. what is the value of A-B ?

Note : if you write 11 , then you will count it as writing '1' twice.

Try more combinatorics problems.

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