NTA Abhyas JEE Main2020MathematicsProbabilityPractice
A special fair cubic die is rolled which has one blue side, two red sides and three yellow sides. The result is the colour of the top side after the die is rolled. If the die is rolled 8 times, then the probability of blue colour coming at least twice is
Options
- A13 × 5 7 6 8
- B6 8 - 13 × 5 7 6 8
- C8 × 5 7 6 8
- D1 - 8 × 5 7 6 8
Correct answer
B. 6 8 - 13 × 5 7 6 8
Step-by-step solution
Let B is the event in which the top side of the die shows blue colour P B = 1 6 = p (Let) Probability of getting a blue colour at least twice = 1 - C 0 8 1 - p 8 - C 1 8 1 - p 7 p 1 = 1 - 5 6 8 - 8 × 1 6 × 5 6 7 = 6 8 - 13 × 5 7 6 8