Webinars SET B - Grade 5-6 - Sunday@4:30-5:30pm EST-Recording Webinar 7

Video Transcription

Video Summary

This webinar for Math Kangaroo Level 5–6 focused on solving logic problems. It opened with a classic “city of truth/city of lies” warm-up, emphasizing the key idea of asking a question that yields the same useful result whether the person lies or tells the truth (e.g., asking which road leads to their own city).<br /><br />The instructors then outlined why logic puzzles matter: they strengthen reasoning, reduce logical errors, and build decision-making skills. Students were reminded to read carefully, re-read for details, and think in “if–then” terms. The session covered several contest-style logic categories: cryptarithms (letters as digits), “certainty” problems (worst-case reasoning), Venn diagram counting, one-to-one correspondence (“whodunnits”), and truth/lie systems.<br /><br />Multiple problems were worked through with polls and explanations. In a cryptarithm, students deduced values using bounds and parity to find X = 6. A fruit-drawing problem used worst-case analysis to determine the minimum draws needed to guarantee an apple and pear of the same color (13). A cat contest Venn-style problem required accounting for overlap to find a minimum of 14 finalists. A professions puzzle used elimination to identify Roberts as the doctor, Smith as the engineer, and Farrell as the musician. An if–then “cat/mouse/cheese” puzzle led to concluding the cat is in the basement and the mouse is in the room. A round-table liar puzzle showed the maximum liars is 9. A dragon-heads puzzle identified the single truth statement as 27 heads (green dragon).<br /><br />The webinar ended with advice: practice full contests for speed and endurance, and systematically test scenarios when stuck.

Keywords

Math Kangaroo Level 5-6

logic puzzles

truth and lies

if-then reasoning

cryptarithms

worst-case analysis

Venn diagram counting

one-to-one correspondence

whodunit logic puzzle

contest problem solving strategies