# Algebra

posted by .

In base 5, how many two digit numbers are there?

• Algebra -

To find the number of 2-digit numbers in base 10, we find:
1. for the first digit, there are 9 choices, as 0 is not admissible.
2. for the second digit, there are all of the 10 choices.

By the multiplication rule, the number of 2-digit base 10 numbers is (10-1)(10)=90.

You can do a similar counting for base 5 numbers.

## Similar Questions

1. ### Calculus

Form two four-digit numbers from the digits 2, 3, 4, 5, 6, 7, 8, and 9, using each digit exactly once, so that the absolute value of the difference of the two numbers is as small as possible.
2. ### algebra

please explaing reversing the digits. Find the product of 2 two digit numbers and reverse the digits and find the product. The products are the same. Does this happen with any pair of two-digit numbers?
3. ### algebra

In base 5, how many two digit numbers are there?
4. ### algebra

all two-digit numbers whose units digits is half the tens digit?
5. ### algebra

all two-digit numbers whose units digits is half the tens digit?
6. ### ALGEBRA 2...

1. Simplify 2.3^5 log base 2.3^1 2. How do you solve this matrix using a graphing calculator AX=B A=9 -3 1 B=-7 X= x 1 1 1 -3 y 16 4 1 21 z 3. How many 4-digits numbers have the thousands digit equal to 2 and the units digit equal …
7. ### college problem solving

a certain two-digit number is 6 less than the sum of its tens digit and 7 times its units digit. if the digits are reversed the number is increase by 27. fin the original two-digit numbers
8. ### Algebra 1

How many two-digit numbers have a tens digit that is greater than the units digit?
9. ### Algebra 1

How many two-digit numbers have a tens digit that is greater than the units digit?
10. ### Math

Think of a five-digit number composed of odd numbers. The thousands digit is two less than the ten thousands digit but two more than the hundreds digit. The tens digit is two more than ones digit which is four less than the hundreds …

More Similar Questions