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We have three cases:
1- Hundreds digit= Tens digit:
In every hundred 9 numbers are in this pattern:
110-112-113-114-115-116-117-118-119
and we have 9 hundreds, so in this case there are 81 numbers.
2- Hundreds digit= Units digit:
In every hundred 9 numbers are in this pattern:
101-121-131-141-151-161-171-181-191
and we have 9 hundreds, so in this case there are 81 numbers!
3- Tens digit= Units digit:
In every hundred 9 digits are in this pattern:
100-122-133-144-155-166-177-188-199,
and we have 9 hundreds, so in this case there are 81 numbers!
Total = 81 + 81 + 81 = 243
Answer is 243
Starting at 100 (the first 3-digit number), I counted all numbers that had exactly two digits that were the same. I did this through 199. There are 27 of these. I then multiplied that result by 9 (to pick up the 200s through 900s).
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How many 6 digit numbers contain exactly different 4 digits?
There are 22680 numbers, excluding those with leading 0s.
How many 5 digits numbers are there whose digits sum to 22?
There are 5460 five digit numbers with a digit sum of 22.
How many whole numbers have exactly four digits?
how many numbers exactly have 4 digits ? 8900, 8999, 9000, 9999
How many 6 digit numbers can be formed using the digits 123456789?
There are 60480 numbers.
How many six digit numbers are there in which no digit is repeated even digits appeared in the even places and odd digits in the odd places and the number is divisible by 4?
There are 5760 such numbers.
How many 3-digit numbers have exactly 2 digits that are the same?
1
How many 3 digit numbers have 2 of the same digits?
Exactly 2: 243 of them.
How many four digit numbers are there which have exactly the same two digits.?
Any pair of digits (not including 0), can be used to generate 14 four-digit numbers. If one of the digits is 0, only seven will start with a non-zero digit.
How many 6 digit numbers contain exactly different 4 digits?
There are 22680 numbers, excluding those with leading 0s.
How many 1 digit numbers can make with 123 digits?
With 123 digits you can make 123 one-digit numbers.
How many 5 digits numbers are there whose digits sum to 22?
There are 5460 five digit numbers with a digit sum of 22.
How many 6 digit numbers contain exactly 4 digits?
Zero; all six digit numbers have six digits. Dude.. i m asking 6 digit numbers, containing only 4 different digits..!! e.g.:123412.. with only 2 digits repeated..!! My guess is: 10*9*8*7*4*3 but I'm also guessing that is wrong- sorry!
How many whole numbers have exactly four digits?
how many numbers exactly have 4 digits ? 8900, 8999, 9000, 9999
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 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 two digit whole numbers are increased by 18 when their digits are reversed?
7 two-digit numbers.
How many 4 digit numbers have 6 as their second digit?
There are 9 digits that can be the first digit (1-9); for each of these there is 1 digit that can be the second digit (6); for each of these there are 10 digits that can be the third digit (0-9); for each of these there are 10 digits that can be the fourth digit (0-9). → number of numbers is 9 × 1 × 10 × 10 = 900 such numbers.
