Multiple choice

In a box of 30 balls, 10 balls are red and 20 green. Three balls have been drawn randomly from the box, in which 2 balls drawn are red and 1 ball is green. Now, another ball is drawn from the box without replacing already drawn balls. What change happens in the probability of a red ball being drawn compared to the same at the beginning?

  1. Does not change

  2. Insufficient data

  3. Decreases

  4. Increases

  5. Becomes half of the initial probability
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is correct, because more red balls have been drawn than green before the trial under question. This has reduced the percentage of red balls in the box.

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