SOLUTION: can there be a perfect square whose digits consist of exactly 4 ones, 4 twos and 4 zeros in any order?

Algebra.Com
Question 1136151: can there be a perfect square whose digits consist of exactly 4 ones, 4 twos and 4 zeros in any order?

Answer by ikleyn(52781)   (Show Source): You can put this solution on YOUR website!
.

Let N =  be such a number.


Since the sum of digits of the number  " N "   4*1 + 4*2 +4*0 = 4 + 8 + 0 = 12  is divisible by 3,

it implies that the number N itself is divisible by 3  (the "divisibility by 3 rule").



In turn, it implies that the number " n "  itself  is divisible by 3.



Then the number    is divisible by 3^2 = 9;  hence, the number N  is divisible by 9.



But the sum of the digits of the number N, which was calculated above as 12, is not divisible by 9.


It contradicts to the "divisibility by 9 rule". 


Hence, such a number N with assigned properties DOES NOT EXIST.


The proof is completed.

The problem is solved.

-----------------

On divisibility rules by 3 and by 9 see the lessons
    - Divisibility by 3 rule
    - Divisibility by 9 rule
in this site.


RELATED QUESTIONS

can there be a perfect square whose digits consist of exactly 4 ones, 4 twos and 4 zeros... (answered by ikleyn)
How many square matrices of 3 X 3 order can be formed by using only 5 ones and 4 zeros? (answered by robertb)
license plates in a particular state are to consist of a 4 digits followed by 2 upper... (answered by ikleyn)
Least no. Of 4 digits which is a perfect... (answered by Timnewman)
Can I get validation on my first part of the problem and help with the second half. I... (answered by richard1234)
In how many ways can a committee of 7 be formed if there are 10 dogs and 15 cats to... (answered by ewatrrr)
How many ways are there to create a 6 digit pin number where exactly 4 of digits are the... (answered by Alan3354,greenestamps,math_helper)
a Particular company,any valid password consists of 8 characters in any order ass follow (answered by richwmiller)
a Particular company,any valid password consists of 8 characters in any order as follow... (answered by richwmiller)