There are 4 green, 2 purple, 1 orange and 5 yellow marbles in a pouch.…

2024

There are 4 green, 2 purple, 1 orange and 5 yellow marbles in a pouch. Shivansh chooses 1 marble at random, records colour & replaces it. He repeats this process 25 times. Which colour did Shivansh probably choose the greatest number of times?

  1. A.

    Green

  2. B.

    Orange

  3. C.

    Purple

  4. D.

    Yellow

Attempted by 1 students.

Show answer & explanation

Correct answer: D

Concept: When an experiment such as drawing a marble at random with replacement is repeated many times, the outcome with the highest single-trial probability is expected to occur most often overall, because expected frequency = probability × number of trials — a larger probability directly gives a larger expected count.

  1. Total marbles in the pouch = 4 (green) + 2 (purple) + 1 (orange) + 5 (yellow) = 12.

  2. Probability of drawing green on any trial = 4/12 = 1/3 ≈ 0.33.

  3. Probability of drawing purple on any trial = 2/12 = 1/6 ≈ 0.17.

  4. Probability of drawing orange on any trial = 1/12 ≈ 0.08.

  5. Probability of drawing yellow on any trial = 5/12 ≈ 0.42.

  6. Comparing the four probabilities: 5/12 (yellow) is the largest, followed by 4/12 (green), then 2/12 (purple), then 1/12 (orange).

Cross-check: Multiplying each probability by the 25 trials gives the expected number of times each colour would be drawn — yellow ≈ 25 × 5/12 ≈ 10.4 times, green ≈ 25 × 4/12 ≈ 8.3 times, purple ≈ 25 × 2/12 ≈ 4.2 times, and orange ≈ 25 × 1/12 ≈ 2.1 times. These expected counts sum to 25, matching the total number of trials, confirming the working is consistent.

Since yellow has both the highest single-trial probability and the highest expected count over the 25 trials, Shivansh most probably chose yellow the greatest number of times.

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