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Another contributor qualified the first answer:
The first answer is correct, except for 39, 48, 57, 66, 75, 84, and 93.
May have missed a few, there's twelve:152433425160105114123132141150
Twelve of them.
10 digits are numbers in the billions.
there are 899 whole numbers that have three digits.
There are twelve possible solutions using the rule you stated... 13,14,17,31,34,37,41,43,47,71,73 & 74
Twelve of them.
May have missed a few, there's twelve:152433425160105114123132141150
10 digits are numbers in the billions.
there are 899 whole numbers that have three digits.
There are twelve possible solutions using the rule you stated... 13,14,17,31,34,37,41,43,47,71,73 & 74
525
Twelve thousand seven hundred written in numerals is 12, 700. This has 5 digits.
Measuring Digits are TWELVE (inches) in the British System and HUNDRED (centimetres) in the Metric System
99999
two
There are 5 numbers of 1 digit, 25 numbers of 2 digits, and 75 numbers of 3 digits. This makes 105 numbers in all.
how many numbers exactly have 4 digits ? 8900, 8999, 9000, 9999