← ⚡ JavaScript World

⚡ Double Trouble

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📖 The mission

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Functions return answers

A function is a tiny machine: it receives inputs, works something out, then returns one answer for the tests to check.

💡 Hint ladder

Multiplication in JavaScript uses the * symbol.
return n * 2;

🧪 Coach checks

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Getting ready

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💬 This function multiplies by 10. Yours will multiply by 2 — same idea!

function timesTen(n) {
  return n * 10;
}

console.log(timesTen(3));   // 30
console.log(timesTen(7));   // 70

📟 It printed:

📟 Output