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qid 11863 · engineering

Question: A penny is to be tossed 3 times. What is the probability there will be 2 heads and 1 tail?

  1. 3/4
  2. 1/4
  3. 1/3
  4. 1/8
  5. 1/16
  6. 1/2
  7. 7/8
  8. 3/8
  9. 2/3
  10. 5/8

Our answer: H. 3/8 Source quote machine-checked (exact quote)

A machine check confirms the quoted words appear at the source. A person has not yet reviewed these. EARN MARKS as a Human Reviewer

How it was answered

Stored method, replayed by code (kind: formula)

card: formula · card sha256 8f5f1c7ecee1e8fa…

Current source

Wikipedia, "Binomial distribution"

https://en.wikipedia.org/wiki/Binomial_distribution

“Suppose a biased coin comes up heads with probability 0.3 when tossed. The probability of seeing exactly 4 heads in 6 tosses is”

Source quote machine-checked (exact quote)

retrieved 2026-09-18T00:09:45.898Z

page text sha256 0dfd46c02a020433… · content sha256 4c3749eaf49bf521…

addendum formula_qid11863.formula_ADDENDUM_source_rs20260918T000945Z · sha256 2b073a5d48d4d7a6… · replaces the version below, addendum sha256 5255b0c2331462fa…

Earlier version (superseded)

https://en.wikipedia.org/wiki/Binomial_distribution

Source weak (http_get_200_text_and_question_terms)

retrieved 2026-09-17T09:30:27.048Z

page text sha256 30e6dd1aea893923… · content sha256 —

addendum formula_qid11863.formula_ADDENDUM_source_bf20260917T093027Z · sha256 5255b0c2331462fa… · replaces the version below, addendum sha256 0ca2249ced17bac9…

Earlier version (superseded)

No public source has been found for this card yet (2 places checked internally).

addendum formula_qid11863.formula_ADDENDUM_source · sha256 0ca2249ced17bac9…

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