Question

Solve this alphanumberic puzzle
A B C D
$\underset{–}{\times 9}$
D C B A

Answer 1

Here, A must be equal to 1, otherwise the product would have 5 digits.
Now, D should be equal to 9 because A is equal to 1.
So, we get
1 B C 9
$\underset{–}{\times 9}$
9 C B 1

Now, B should be equal to 0 or 1, otherwise the product would have 5 digits.
If B = 1, then C = 0, otherwise the product would have 5 digits.
But 1109 X 9 = 9981, which isn't correct as per the given condition.
So B = 0. Then 9 X D = 9 X 9 = 81, so 8 + 9 X C ends with a 0 (as B = 0) which is possible only when C is equal to 8.
Therefore,
1 0 8 9
$\underset{–}{\times 9}$
9 8 0 1

Hence, ABCD is 1089.