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Lesson 1 of 9

A guess you can test

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5 min

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Why does a puri puff? Everyone has a guess, a claim that may be right or wrong. Which guesses can you test?

The claim: "Thicker puri, slower puff."
Step 1 of 4
  1. The claim: "Thicker puri, slower puff."
  2. A test can give two readings.
  3. "Faster" goes against the claim.
  4. "Puffs, or not" fits both, so nothing crosses it.

A guess can be tested when a test could show it wrong.

A hypothesis is a claim that a test can check. A test must be able to show it wrong. This is because a claim that fits every result teaches nothing.

To observe is to notice with your senses.

The rule

A hypothesis is a claim a test could show to be wrong. It is often a guess about why, or about what will happen. It names something you can observe or measure. A claim nothing could go against is not a hypothesis.

Sort seven claims. Drag each to a lane. Ask: could a test show it wrong?

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