Homework Help: math

Posted by peter on Wednesday, December 21, 2011 at 1:39pm.

Find digits A and B in the number below so the folling condition are true. The 5-digit number must be divisible by 4. The 5-digit number must be divisible by 9. Digit A cannot be the same as Digit B.

12A3B

Explain the steps you followed to solve the problem.

math - Steve, Wednesday, December 21, 2011 at 4:34pm
If a number is divisible by 9, the sum of its digits is too. That is, they must add up to a multiple of 9.

6+A+B = 9k
so,
A+B = 9k-6
The most they can be is 18, so they must add up to 12 or 3.

3B must be a multiple of 4, since xxx00 is. So, 3B must be 32 or 36. Can't be 36, because that would make B=6 so A=6.

So, B = 2 and A=1

12132 = 4*3283 = 9*1348

Answer this Question

Related Questions

Algebra math. - 1) the sum of the digits of a two digit number is 9. The value ...
math - Find a six-digit even number containing no zeros and no repeating digits ...
math - What mystery number has 8 digits; none of the digits are the same. It is ...
math - Using the numbers 1 through 9 with no repeats, find a 9 number such that...
Math (Reiny) - Regarding my question below, when the question talks about digits...
4th grade math - Find the mystery number. It is a 4 digit odd number. All the ...
algebra - A number consists of two digits. The sum of twice the tens digit an 5 ...
math - *The number has 8 digits, none of the digits are the same. *It is evenly ...
math - find the mystery number, it is a 4 digit odd number, all the digits are ...
Digit Problems - If the tens digit of a two-digit number is subtracted from the ...

For Further Reading

First Name:
School Subject:
Answer: