The numbers 1 through 9 are written in separate slips of paper, and the slips are placed into a box. Then, 4 of these slips are drawn at random.
What is the probability that the drawn slips are "1", "2", "3", and "4", in that order?
A) 0.007944
B) 0.000331
C) 0.00794
D) 0.19056

Question

Quizplus · Accepted Answer

The probability of drawing "1", then "2", then "3", then "4" in that order is calculated by multiplying the probabilities of drawing each number in sequence. For the first draw, the probability of drawing "1" is 1/9. Assuming "1" is drawn, the probability of then drawing "2" is 1/8, since one slip is already removed. Similarly, the probabilities for "3" and "4" are 1/7 and 1/6, respectively, after the preceding numbers have been drawn. Multiplying these probabilities gives (1/9) * (1/8) * (1/7) * (1/6) = 1/3024, which is approximately 0.000331.

The Numbers 1 Through 9 Are Written in Separate Slips