Question

Jack puts the letters of the word BUILDING on pieces of paper and puts the pieces in a bag. He draws two letters without looking. The first piece of paper is not replaced before the second piece is drawn. What is the probability that Jack draws an I twice?

Answer 1

There are 8 letters.

2/8 to get "i" on the first draw since there are two "i" out of the 8 letters.

We have only 7 letters left.

1/7 to get "i" on the second draw (no replacement)since we got "i" on the first draw. There is only 1 "i" left out of the 7 letters.

Multiply the probabilities for the two draws to get the total probability.

2/8 * 1/7 = 2/56

1/28

The probability is 1/28