Statisticshard · Past Paper
An urn contains 4 red, 5 blue and 6 green balls. Three balls are drawn at random. What is the probability that all are of different colors?
A4/91
B24/91
C1/455
D12/455
✓ Correct Answer: B — 24/91
Ways to pick 1 of each = 4*5*6 = 120. Total ways = 15C3 = (15*14*13)/(3*2*1) = 455. 120/455 = 24/91.
Share this question
More from Statistics
- Three dice are thrown. What is the probability of getting the same number on all three?
- Which of these is the most frequent value?
- Find the mean of 1, 2, 2, 3, 3, 3.
- The mean of five numbers is 20. If one number is excluded, the mean becomes 15. What is the excluded number?
- If the mean of x and 1/x is M, what is the mean of x^2 and 1/x^2?