Probability

If two different numbers are taken from the set {0, 1, 2, 3, ..., 10}; then the probability that their sum as well as absolute difference are both multiple of 4, is

  1. 6/55
  2. 12/55
  3. 14/45
  4. 7/55

Solution

Consider two sequences: 0, 4, 8 and 2, 6, 10

Take both numbers from either of these sequences.

Hence, probability = (3C2 + 3C2)/11C2

= 6/55

The correct option is A.