All the digits become numbers when used as a number.(ii) There are 90 numbers of two digits. The smallest two-digit number is 10 and greatest two-digit number is 99. In a two-digit number, one digit is placed at ten’s place and the other at one’s place.
A digit is an element of a set that, taken as a whole, comprises a system of numeration. Thus, a digit is a number in a specific context. In the decimal (base-10) Arabic numbering system, the digits are the elements of the set {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}. In the binary number system, the digits are the elements of the set {0, 1}. This system is used by computers because the two digits can represent the logic low and high states. The term binary digit is compressed to  bit  in computer parlance. We know that all the numbers are formed with the digits 1, 2, 3, 4, 5, 6, 7, 8, 9 and 0. Some numbers are formed with one digit, some with two digits and some with many digits. (i) There are 9 numbers of one digit. The smallest one-digit number is 1 (one) and greatest one-digit number is 9. All the digits become numbers when used as a number. (ii) There are 90 numbers of two digits. The smallest two-digit number is 10 and greatest two-digit number is 99. In a two-digit number, one digit is placed at ten’s place and the other at one’s place. Given only two digits, we can form only two different two-digit numbers. (a) Let the given digits be 4 and 9. (iii) There are 900 numbers having three digits. The smallest three-digit numbers is 100 and the greatest three-digit number is 999. Given 3 digits, we can form 6 three-digit numbers. (a) Let the given digits be 2, 5 and 6. Digit. A digit is a single symbol used to make numerals. 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 are the ten digits we use in everyday numerals. Example: The numeral 153 is made up of 3 digits (1, 5 and 3). Example: The numeral 46 is made up of 2 digits (4, and 6). Example: The numeral 9 is made up of 1 digit (9). So a single digit can also be a numeral. So digits make up numerals, and numerals stand for an idea of a number. Just like letters make up words, and words stand for an idea of the thing.  Adding double-digit numbers is just like adding single-digit values, you just go through the process of addition more than once. When you add two-digit numbers you add the columns together, not the entire numbers. For example, you wouldn't want to try and add 78 and 57 as complete numbers in your head. Any number added to zero is itself. The next challenge in adding two-digit numbers will have you adding numbers that involve carrying or regrouping. We already spoke a bit about carrying in an earlier tutorial. If the sum from ones column is greater than nine (9), you carry the 1 to the next column on the left. Since you need some math help, a one digit number is a number with one digit, such as 1, 2, 3, 4, etc. A two digit number is a number with two digits, such as 23, 71, 87, etc. … And it seems that you need some grammar help, too. To multiply two digit numbers, multiply each place value of a factor by each place value digit and add the results. Edit. Share to: 1  How Computers Handle Numbers If you are going to start coding in a programming language such as Visual Basic, it is important to learn some of the basics involved. For example, in the decimal number 2609.37, the number 2 is the thousands digit, the number 6 is the hundreds digit, the number 0 is the tens digit, the number 9 is the ones digit, the number 3 is the tenths digit, and the number 7 is the hundredths digit. In the binary number system, the digits are the elements of the set {0, 1}. This system is used by computers because the two digits can represent the logic low and high states. The term binary digit is compressed to  bit  in computer parlance. In a given numeral system, if the base be an integer, the number of digits required would always equal to the absolute value of the base. For example, the decimal system (base 10) has ten digits (0 through to 9), whereas binary (base 2) has two digits (0 and 1).  Place Values Numbers, such as 84, have two digits. Each digit is a different place value. The left digit is the tens' place. It tells you that there are 8 tens. The last or right digit is the ones' place which is 4 in this example. Therefore, there are 8 sets of 10, plus 4 ones in the number 84. 8 4 | |__ones' place |_________tens' place Return to Top. It tells you that there are 8 tens. The last or right digit is the ones' place which is 4 in this example. Therefore, there are 8 sets of 10, plus 4 ones in the number 84. 8 4 | |__ones' place |_________ I think this is the easiest: Count the number of three-digit numbers: The first digit can be 1-9; the second and third digits can be … 0-9. So, there are 9 choices for the first digit and 10 choices for the second and third digits. 
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what is a two digit numbers