Question 1085119: If repetition is not allowed,how many 4 digit numbers can be formed with the integers 0,1,3,4,5,6,7,8,9? How many of these are between 2000 and 8000?
Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! If repetition is not allowed,how many 4 digit numbers can be formed with the integers 0,1,3,4,5,6,7,8,9?
If leading zeroes are not allowed, ie, 0134, then:
The 1st digit is 1 of 8.
The 2nd digit is 1 of 8.
The 3rd digit is 1 of 7.
The 4th digit is 1 of 6.
8*8*7*6 = 2688 numbers.
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How many of these are between 2000 and 8000?
The 1st digit is 1 of 5.
The 2nd digit is 1 of 8.
The 3rd digit is 1 of 7.
The 4th digit is 1 of 6.
5*8*7*6 = 1680 numbers
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