Carcass wrote:
OE
Let the two-digit positive number be 𝑚 = 𝐴𝐵 where A is the tens digit and B is the
unit digit. Hence, the other two-digit number which will be formed by interchanging
the digits of 𝑚 will be 𝑛 = 𝐵𝐴
Now, 𝑚 = 𝐴𝐵 = 10𝐴 + 𝐵
And, 𝑛 = 𝐵𝐴 = 10𝐵 + 𝐴
Thus, the difference, 𝑚 − 𝑛 = 10𝐴 + 𝐵 − 10𝐵 − 𝐴 = 9𝐴 − 9𝐵 = 9(𝐴 − 𝐵)
Hence, the difference will always be the multiple of 9.
Therefore, among the options the possible values the difference can have will
be 18, −9
Ans. (C, E)
Dear Sir,
The OA is showing only answer C as the correct answer which is wrong. Please recheck and make necessary adjustments.