LOGIC · FREE TO PLAY

Set Intersection

Find the element shared by two sets.

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How to play Set Intersection

  1. Find the element shared by two sets.
  2. Read the prompt carefully and choose an answer, or type into the answer field.
  3. After checking, read the explanation. Use “Next round” to continue.
  4. Complete ten rounds for a score out of 100. Restart creates a fresh session.

A worked example

Which value appears in BOTH sets? {20, 6, 14} ∩ {16, 15, 6}

the answer is 6. Look for the shared member.

A useful way to practice

Write down what is known and what is only assumed. Look for constraints that eliminate possibilities, then test a small next step. A wrong answer is useful information about the strategy you chose.

What your result means

This is a recreational logic activity. Results describe performance on this particular task, with this device and these rules. They are not a clinical assessment, IQ score or promise of improvements in daily life. Your best result and recent sessions stay in this browser; no account is required.

Is Set Intersection free?

Yes. You can play the full activity without a payment, download or account.

Can I use a keyboard?

Use Tab to focus buttons and Enter or Space to activate them. Answer fields accept normal typing. The maze also supports arrow keys. Timed tests will differ between touch, mouse and keyboard input.

Why did my result change?

Practice, a different generated puzzle, distractions and input timing all affect results. Compare several sessions rather than drawing a conclusion from one attempt.