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The question can be re-stated as asking for the total number of permutations that can be derived from the following two groups of digits: AAABCD and AABBCD, where A, B, C and D are different.
The number of ways of choosing the digit A, to be used three times, out of the ten digits {0, 1, 2, ... 9} is 10. Having done that, the number of ways of selecting 3 from the remaining 9 digits is 9C3 = (9*8*7)/(3*2*1) = 84. Thus there are 10*84 = 840 combinations of the form AAABCD. You now need all the distinct permutations of these 6 digits. The total number of permutations of 6 digits is 6! but because 3 of the digits are the same, these permutations are not all distinct. In fact, there are 6!/3! = 120 distinct permutations. That makes a total of 840*120 = 100800 such numbers.
Next, the number of ways of choosing the digits A and B, each to be used twice, out of the ten digits {0, 1, 2, ... 9} is 10C2 = (10*9)/(2*1) = 45. Having done that, the number of ways of selecting C and D from the remaining 8 digits is 8C2 = (8*7)/(2*1) = 28. Thus there are 45*28 = 1260 combinations of the form AAABCD. You now need all the distinct permutations of these 6 digits. The total number of permutations of 6 digits is 6! but because 2 pairs of these digits are the same, these permutations are not all distinct. In fact, there are 6!/(2!*2!) = 180 distinct permutations. That makes a total of 1260*180 = 226800 such numbers.
The grand total is, therefore, 100800 + 226800 = 327600 6-digit numbers made from 4 distinct digits.
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How many different 2 digit odd numbers can be formed from the digits 1 through 8 if no digits are repeated in a number?
36
How many 8 digit numbers can be formed by the digits 1234567890?
u culd make 80
How many four digit numbers can be formed out of 123 if a digit can be repeated?
There are 3 values (1, 2, 3) for each of the 4 digits. Therefore, there are 3*3*3*3 or 81 four digit numbers that can be formed.
How many 4 digit numbers can be formed by the digits 1234567890?
Oh, what a happy little question! With the digits 1-9 and 0, you have 10 options for each digit in a 4-digit number. So, you can form 10 x 10 x 10 x 10 = 10,000 different 4-digit numbers. Isn't that just delightful? Just imagine all the beautiful combinations you can create!
How many even 3-digit numbers can be formed from the digits 1 2 3 and 5 if each digit can be used only once?
The final digit must be a 2 to form an even number. The first digit may be any of three remaining digits (1, 3, 5) while the second digit may be any of the two remaining digits. All together, that makes 3*2 = 6 distinct even numbers.
How many 4 digit numbers can be formed from digits 123456789?
There are 7,290 different 4-digit numbers that can be formed from the digits 1-9 without repetition.
How many different four-digit numbers can be formed from the digits 0 through 9?
10,000
How many different 2 digit odd numbers can be formed from the digits 1 through 8 if no digits are repeated in a number?
36
How many different 5 digit numbers can be formed from the digits 0 to 9?
100000 - including numbers with leading 0s
How many 4 digit numbers can be formed by the digits 1 2 3 4 using each digit only once?
24 different numbers.
How many different three digit numbers can be formed from the digits 0 through 9 if the first digit must be odd and the last digit must be even?
5 x 10 x 5 = 250 different numbers, assuming there is no limit to each digits' use.
How many different four digit numbers can be formed by rearranging digits 2013?
how make the answer im don/now
How many 3 digit numbers can be formed from the digits 357 with any digit repeated?
27 three digit numbers from the digits 3, 5, 7 including repetitions.
How many different 4-digit numbers can be formed from the digits of 0 2 4 and 7?
192, including ones containing repeat digits.
How many six digit numbers can be formed using the digits 0123456789 Example equals 123456 or 098765?
The number of six digit numbers that you can make from ten different digits ifrepetitions of same digit on the six digit number is allowed is 1 000 000 numbers(including number 000 000).If no repetitions of the the same digit are allowed then you have:10P6 = 10!/(10-6)! = 151 200 different six digit numbers(six digit permutations form 10 different digits).
How many 3-digit numbers can be formed from the 5 digits 1 2 3 4 5 if no digit may be repeated in a number?
60 different numbers can be formed from the digits {1, 2, 3, 4, 5} is no repeats are allowed Any of the first digits can be chosen for the first digit, leaving 4 for the next and 3 for the final digit. Thus there are 5 × 4 × 3 = 60 different possible such permutations of 3 digits from the 5.
How many 4 digit numbers can be formed from the digits 7341 if none of the digits can be repeated?
24
