Junior Cycle · Number Theory ⏱ Tested in 1 exam question since 2023 Lesson 3 of 5

JCHL Number Theory 3: Rounding off and Scientific Notation

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You’ll learn

  • Scientific notation is a × 10ⁿ where a is between 1 and 10
  • Big number → positive power; small number (less than 1) → negative power. The power = how many places you moved the decimal
  • Rounding: look at the next digit — 5 or more rounds up, less than 5 rounds down

Formula used

Scientific notation: a × 10ⁿ with 1 ≤ a < 10

n is positive for big numbers, negative for small ones

Most recent exam questions

  • 2023 Q1(a)
  • 2023 Q1(b)

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