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. Your subject and verb do not agree; it should be "What are one and two digit numbers?".
You're welcome...
xD
A one digit number is a number with only one number. For example: 12 is a two digit number. It has two numbers. 3 is a one digit number because it only has one number.
The greatest sum of two two-digit numbers occurs when you add the largest two-digit numbers together. The largest two-digit number is 99. Therefore, the greatest sum of two two-digit numbers is 99 + 99, which equals 198.
There are 21 two-digit prime numbers.
There are 17 of them.
In the number 65437, the last two digits are 37 - a digit is one single character in a string of numbers.
There are 28706 such combinations. 5456 of these comprise three 2-digit numbers, 19008 comprise two 2-digit numbers and two 1-digit numbers, 4158 comprise one 2-digit number and four 1-digit numbers and 84 comprise six 1-digit numbers.
A one digit number is a number with only one number. For example: 12 is a two digit number. It has two numbers. 3 is a one digit number because it only has one number.
There can only be one largest two-digit prime number.
The greatest sum of two two-digit numbers occurs when you add the largest two-digit numbers together. The largest two-digit number is 99. Therefore, the greatest sum of two two-digit numbers is 99 + 99, which equals 198.
There are 21 two-digit prime numbers.
2,4,6,8,10,12,14,16,18
I believe that the numbers One and Nine fit the bill as they would be 1x9= 9 and 1+9=10.
20 and 30 All numbers have at least one common factor.
The answer will depend on how many digits there are in each of the 30 numbers. If the 30 numbers are all 6-digit numbers then the answer is NONE! If the 30 numbers are the first 30 counting numbers then there are 126 combinations of five 1-digit numbers, 1764 combinations of three 1-digit numbers and one 2-digit number, and 1710 combinations of one 1-digit number and two 2-digit numbers. That makes a total of 3600 5-digit combinations.
There are 17 of them.
In the number 65437, the last two digits are 37 - a digit is one single character in a string of numbers.
There are two single-digit numbers less than 10 which are cubes of whole numbers. These are 13 (one cubed = 1) and 23 (two cubed = 8).