Answer :
1/21 * 1/20 = 1/420 that is the probability that you are chosen first.
Probability of your friend chosen first = 1/420 also.
So the required probability = 1/420 + 1/420 = 1/210 Answer
Its D
Probability of your friend chosen first = 1/420 also.
So the required probability = 1/420 + 1/420 = 1/210 Answer
Its D