What is the smallest number that must be added to 19487161 so that it is divisible by 11?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 10
The given number = 19487161
A number is divisible by 11 if the difference between the sum of its digits at odd places and the sum of its digits at even places is either 0 or a multiple of 11.
The alternating sum of the digits, starting from the rightmost digit and alternating between addition and subtraction = 1 - 6 + 1 - 7 + 8 - 4 + 9 - 1 = 1
Here, 1 is the remainder when 19487161 is divided by 11.
So, we need to add 10 to the number to make the remainder 0.
Therefore, the smallest number that must be added to 19487161 to make it divisible by 11 is 10.