NTA Abhyas JEE Main2020MathematicsProbabilityPractice
If 4 distinct numbers are chosen randomly from the first 100 natural numbers, then the probability that all 4 of them are either divisible by 3 or divisible by 5 is
Options
- A6 C 4 100 C 4
- B33 C 4 100 C 4
- C20 C 4 100 C 4
- D47 C 4 100 C 4
Correct answer
D. 47 C 4 100 C 4
Step-by-step solution
Total cases = 100 C 4 Numbers which are divisible by either 3 or 5 = n 3 + n 5 - n 3 ∩ 5 = 33 + 20 - 6 = 47 Favourable cases = 47 C 4 Hence, required probability = 47 C 4 100 C 4