Logical reasoning · lesson 11 of 30 · free

Ranking in a row — Logical reasoning for kids

Riya is 7th from the left and 12th from the right. How many children are in the row? Draw it once and you will see why the answer is not 19.

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How to think it through

Counted twice — “counting from both ends counts the child twice, so take 1 away”

  1. Total = position from the left + position from the right − 1.
  2. Position from the right = total − position from the left + 1.
  3. Children between two people: change both positions to “from the left”, then (bigger − smaller − 1).

Use it for: Ranking questions in reasoning tests, class ranks, and queues.

Worked example: Riya is 7th from the left and 12th from the right in a row of children. How many children are in the row? → 18

  1. Counting from both sides counts Riya twice: 7 + 12 − 1.
  2. 7 + 12 − 1 = 18.

Check: 6 children on her left + Riya + 11 on her right = 18 ✓

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✏️ Practice

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🏁 Lesson 11 test

20 questions. Check each answer, then go to the next one. Get 16 or more right to pass.

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🖨️ Ranking in a Row Worksheet

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