10 digits are numbers in the billions.
there are 899 whole numbers that have three digits.
Actually, it doesn't. At least, it is not 10 digits all over the world. For example, in Bolivia, the mobile phone number has only 8 digits. The number of digits required (for any particular country) can depend on the following:The number of mobile phones (or similar devices) used. If in some country you have, say, 5 million mobile devices, you need at least seven digits.Mobile numbers may have to start with certain digits. This may require an additional digit. In the above example, if in a country all mobile phone numbers start with 6, 7 or 8, then 7 digits are no longer enough - the minimum requirement is 8 digits.The numbers may be organized so that the first few digits identify the phone company, or the geographical region. This also tends to increase the number of digits, since some areas will have few numbers, while others will have many.
99999
two
10 digits are numbers in the billions.
there are 899 whole numbers that have three digits.
5
525
-99
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.
Actually, it doesn't. At least, it is not 10 digits all over the world. For example, in Bolivia, the mobile phone number has only 8 digits. The number of digits required (for any particular country) can depend on the following:The number of mobile phones (or similar devices) used. If in some country you have, say, 5 million mobile devices, you need at least seven digits.Mobile numbers may have to start with certain digits. This may require an additional digit. In the above example, if in a country all mobile phone numbers start with 6, 7 or 8, then 7 digits are no longer enough - the minimum requirement is 8 digits.The numbers may be organized so that the first few digits identify the phone company, or the geographical region. This also tends to increase the number of digits, since some areas will have few numbers, while others will have many.
how many numbers exactly have 4 digits ? 8900, 8999, 9000, 9999
A Pakistani mobile number looks like +92 3XZ YYY YYYY. That's a total of 12 digits, including the country code, or 10 digits for the national significant number. Within Pakistan, you dial the trunk prefix 0 followed by the 10-digit number, for a total of 11 digits.
11