my 4th grader was given this question in class for homework good luck.?

Question

a b c d e x 4 = e d c b a

Answer 1

Guys, this is a 4th grader's homework, think about it. There's no algebra in 4th grade math. Unless I am very much mistaken, the letters are for place values, not variables.

It took me a while, but after a little deduction, I came up with the answer.

a=2, b=1, c=9, d=7, e=8

21978x4=87912

Answer 2

The question is basically saying if I take the fifth digit "e" and muliply it by 4, that whatever number the digit is will show up in the first digit in the answer, so if "e" was "2", then

_ _ _ _ 2 X 4 = 2 _ _ _ _ _

I'm not sure if there is a mathematical way to solve a problem like this, other than just trial and error. As you do this, you may have some theories. (For example "e" could not equal 0, since that would mean that "a" has to be 0 as well.)

Good luck!

Answer 3

I think I know how to start but can't finish it.

Think of the letter in the first place to the left as being the number of ten-thousands in the required number. Then think of the number next to it as being the number in the thousands. And so one until the last number (all the way to the right) is the number of ones. When you add them all up and multiply that total by four you get another number that has the same 5 digits in it but transposed. Again the letter on the left is the number of ten-thousands in the desired number. and so on.

The problem is that you have 5 variables but only one equation. So all we have found is a way to tell which of the possible 99 thousand answers is the right one after we look at every one of them. We need more clues.

I think we can get some help by realizing that the first digit on the left hand number must be 8 and that makes last digit on the right hand number be 2 (which is also then the last digit on the left hand number). If that is correct then there are only a 445 possibilities to slog through since each number we get uses up 1 of the 10 possibilities. That is still a lot of slogging but I am out of clues.

Answer 4

Well it appears that all the teachers of all the schools have given all their students the same problem yesterday.This is the fifth time I am giving the answer.
It is 21978 X 4=87912

Answer 5

then the only answer is that

e d c b a

all together = 0

if abcde x 4 = edcba, then 0 x 4 = 0

Answer 6

Interesting...thats the second post today on that question....the answer is 4abcde

doesn't matter what order you multiply the numbers...they are always going to equal the same.



SouthCal is right it is 0

Answer 7

I'm glad that I'm not in 4th grade!! I can hardly help my 7 year old with his math anymore.

Answer 8

x = 1/4 ?

Are we solving for "x"?

Answer 9

What is the question?

Answer 10

CJ E is my hero