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Question

Assume each letter in the following formula represents a unique digit: (for example, ABCD could be the number 1234)

ABCDE X 4 = EDCBA

What is the number represented by the digits EDCBA?

Answer 1

ABCDE is 21978, and EDBCA 87912.

Answer 2

Solutions:

Since ABCDE is a five-digit number, A is not equal to 0.
Since the product has at most 5 digits then in the multiplicand A = 1 or 2;
..........and in the product E is greater than or equal to 4.

From the units place, 4 x E is even, therefore with "A = 1 or 2" (as previously mentioned), then A = 2.
..........which in turn implies that E = 3 or 8.

This, together with "E is greater than or equal to 4" (as previously mentioned), implies that E = 8.

So,

.......3
2 B C D 8
..........x 4
________
8 D C B 2

Looking at the tens place, B is odd. And looking at the thousands place, B is 1 or 2 (no "carrying" in the thousands place). But because B is odd, then B = 1.

...b a 3
2 1 C D 8
..........x 4
________
8 D C 1 2

From the tens places D = 2 or 7.
On the other hand, in the hundreds place b = 0, 0, 2 or 3; so that D is not equal to 2. Therefore D = 7.

...3 3 3
2 1 C 7 8
.........x 4
________
8 7 C 1 2

In the hundreds place, since 3 is "carried" to the thousands place, C must be a digit such as (4 x C) + 3 is greater than 30. So C must be 7, 8 or 9. We use trial and error to find the value of C, and found that only C = 9 satisfies the multiplication. So ABCDE stands for 21978.

...3 3 3
2 1 9 7 8
........x 4
________
8 7 9 1 2

hope it helps :)

Answer 3

THE ANSWER IS 21978

21978 * 4 = 87912

Answer 4

try it out using yr calculator...
gud luck~!