--- title: 100 random chords, how many intersections? | daily.dev description: A math puzzle asking for the expected number of intersection points when 10 or 100 random chords are drawn inside a circle. The post clarifies the definition... canonical: https://daily.dev/posts/100-random-chords-how-many-intersections--hhmizspwa twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: 100 random chords, how many intersections? | daily.dev og:description: A math puzzle asking for the expected number of intersection points when 10 or 100 random chords are drawn inside a circle. The post clarifies the definition... og:url: https://daily.dev/posts/100-random-chords-how-many-intersections--hhmizspwa og:image: https://api.daily.dev/og/posts/hHMIzSPwa.png og:image:alt: 100 random chords, how many intersections? og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # 100 random chords, how many intersections? **[3Blue1Brown](https://daily.dev/sources/3blue1brown)** · 1 min read · 1 upvotes · 0 comments ## Summary A math puzzle asking for the expected number of intersection points when 10 or 100 random chords are drawn inside a circle. The post clarifies the definition of a 'random chord' to avoid Bertrand's paradox: each chord is formed by picking two points independently and uniformly on the circle's circumference. The puzzle hints at a connection to problems from the previous two months. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: --- Tags: [#math](https://daily.dev/tags/math), [#statistics](https://daily.dev/tags/statistics) [View this post on daily.dev](https://daily.dev/posts/100-random-chords-how-many-intersections--hhmizspwa) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"100 random chords, how many intersections?","url":"https://daily.dev/posts/100-random-chords-how-many-intersections--hhmizspwa","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/100-random-chords-how-many-intersections--hhmizspwa"},"datePublished":"2026-06-16T18:09:51.611Z","dateModified":"2026-09-14T06:34:33.367Z","description":"A math puzzle asking for the expected number of intersection points when 10 or 100 random chords are drawn inside a circle. 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