Lesson 4 of 4 · 9 minutes

Combining conditions: and / or

A decision can depend on more than one thing. Logical operators combine conditions.

&& means and: both conditions must be true. || means or: at least one must be true.

For age >= 13 && age <= 19, 13 and 19 count. But 12 and 20 do not. Check the edge values carefully. That is where many mistakes hide.

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Test 13, 12, 19, and 20. Watch where the output changes.

Quick check

When is && true?

When both conditions are true.When at least one is true.When exactly one is true.

Choose one answer.

With age >= 13 && age <= 19, does age 19 count?

Yes. <= 19 includes 19.No. The cutoff is excluded.Only if you use ||.

Choose one answer.

You can now combine conditions with and and or — and you know to watch the edges.