Multiple choice

Directions: The question given below is followed by three statements numbered I, II and III. Read all the statements carefully and decide which of them is/are sufficient to answer the given question. Choose the correct alternative accordingly. What is the probability of picking 1 red and 1 white ball from a bag containing balls of three colours without replacement? I. The bag contains red, white and blue balls in the ratio 3 : 5 : 7. II. The bag contains 75 balls. III. The number of red balls in the bag is 40% less than number of white balls.

  1. Only I

  2. Only II and III

  3. Only I and III

  4. Only I and II

  5. Even I, II and III together are not sufficient.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

To find the probability of picking 1 red and 1 white ball, we need the total number of balls and the count of each color. Statement I gives the ratio (3:5:7), and Statement II gives the total (75). With these, we can find the exact number of red, white, and blue balls, which is sufficient.

AI explanation

To find the probability of picking 1 red and 1 white ball without replacement, the exact number of red and white balls is required. Statement I provides the ratio of red, white, and blue balls as 3 to 5 to 7, and statement II provides the total number of balls as 75. Using the total of 75 balls and the ratio parts summing to 15, we calculate the red balls as 15 and the white balls as 25, which is sufficient to find the probability. Statement III provides redundant or insufficient data on its own without the total count. Therefore, only statements I and II together are sufficient to answer the question.

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