In each of the following numbers, what should be the missing digit in the indicated place such that the number is a multiple of 11?

• A. 8
• B. 3
• C. 2
• D. 5

Answer: (A)

Divisibility of 11: If the difference of the sum of the digits at odd places and the sum of the digits at even places of a number is zero or a multiple of 11, then that number is divisible by 11.As per divisibility rule of 11, difference = (x + 21) - 18 = x + 3=> x + 3 = 11 => x = 8