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How many 7 digit phone numbers are available if a digit can only be used once and the first number can not be 0 or 1?
560135
Micron: wished you had posted the logic. As I see it, the first can be one of 8 digits. The second number can be 0 or 1 but not the same as the first (9 to choose from). The third cannot be the same as either of the first two (8 to choose from), etc. Thus it would be 8*9*8*7*6*5*4=483,840
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How do 3 digit numbers compare to 4 digit numbers?
3 digit numbers are lessthan 4 digit numbers
What is First 3 digit number?
The first three-digit number is 100. It is the smallest integer that has three digits, starting from 1 and followed by two zeros. Numbers below 100, such as 99, are considered two-digit numbers.
Name a 10 digit Number such that the first digit on the left tells how many 0 are in the numbers?
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How many different 7-digit telephone members are possible if the first digit can not be zero and no digit repeat?
There are 10 possible numbers that can be chosen. Since the first digit can't be 0, there are 9 selections for the first digit. The second number can include a 0, but can't include the first number chosen, so there are 9 selections for the second digit. Then there are 8 digits for the next number, 7 digits for the next number, and so on. Total telephone numbers are: 9*9*8*7*6*5*4 = 544320 phone numbers.
What is the smallest three digit number divisible by the first three prime number and the first number three composite numbers?
120
