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A bag contains 100 pencils that are either red or green - OCR - GCSE Maths - Question 20 - 2019 - Paper 1

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A bag contains 100 pencils that are either red or green. Describe a method you could use to estimate the number of red pencils in the bag without looking into the b... show full transcript

Worked Solution & Example Answer:A bag contains 100 pencils that are either red or green - OCR - GCSE Maths - Question 20 - 2019 - Paper 1

Step 1

Method to Estimate Number of Red Pencils

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Answer

  1. Random Sampling: Take one pencil out of the bag at random, without looking.

  2. Record the Color: Observe and note the color of the pencil you have taken out.

  3. Return the Pencil: Place the pencil back into the bag to ensure the total count remains 100.

  4. Repeat: Continue this process multiple times (e.g., 30 or 50 times). Each time, keep a count of how many red pencils are drawn versus green ones.

  5. Calculate Proportion: After the sampling, use the following formula to estimate the number of red pencils:

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