Question:
The sum of a two-digit number and the number obtained by reversing the digits is always divisible by———–.
Solution:
11
Let ab be any two-digit number, then the number obtained by reversing its digits is ba.
Now, ab + ba = (10a + b) + (10b + a) = 11a + 11b = 11(a + b)
Hence, ab + ba is always divisible by 11 and (a + b).
Click here to get exam-ready with eSaral
For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.