A six-digit number is divisible by 33. If 21 is added to the number, then the new number which formed is also divisible by:
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 3.
Number (N) = 33k where k is an integer
New number (N') = 33k + 21 = 3(11k + 7)
Hence, the new number is divisible by 3.