Question:
A four-digit number aabb is divisible by 55. Then, possible value(s) of b is/are
(a) 0 and 2
(b) 2 and 5
(c) 0 and 5
(d) 7
Solution:
(c) It is given that, aabb is divisible by 55. Then, it is also divisible by 5.
Now, if a number is divisible by 5, then its unit digit is either 0 or 5.
Hence, the possible values of b are 0 and 5.