Q21 of 31 Page 7

Using the digits 0, 1, 2, 2, 3 how many numbers greater than 20000 can be made?

For the number to be greater than 20000 there are only two possibility.


Case 1: When numbers start with 2.



5th place will be fixed with 2.


Remaining four places can be filled in 4! ways now.


So total number of ways fir a number to start with 2 is 4! = 4× 3× 2× 1


= 24 ways


Case 2: When numbers start with 3.



5th place will be fixed with 3.


Since number is repeating so we use the formula .


Here p1= 2 as number 2 is repeated two times.


Now the remaining places can be filled in ways.



= 12 ways


So total ways = 24 + 12


= 36 ways


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