Question

Em uma caixa há 11 bolas vermelhas e 7 azuis. Ao escolher 4 bolas aleatoriamente, qual a probabilidade de serem todas vermelhas? (A) 1 7 . (B) 7 102. (C) 11 102. (D) 7 18 (E) 11 18

Answer 1

Answer: C. 11/102

Explanation:

Given Data:

Red ball = 11

Blue ball = 7

Total no of balls = 18

What is the probability that choosing 4 balls all are red.

1. Probability of picking a red ball

= 11/18

2. Probability of picking a blue ball

= 7/18

3. Probability of picking 4 red balls in a roll.

= 11/ 18 * 10/17 * 916 * 8/15

= 11/102

Or

10.8% chance of all 4 balls being red.