ACT Preparation / Unit 7 ACT 0608 short lesson, about 20 seconds
Scientific Notation
Captions available
The idea
Scientific notation writes a number as a × 10ⁿ, with 1 ≤ |a| < 10 and n an integer; small numbers take a negative n.
In practice
45,000,000 = 4.5 × 10⁷; 0.0062 = 6.2 × 10⁻³.
Where people slip
The leading number must be at least 1 and less than 10, so 45 × 10⁶ is equal but not in scientific notation.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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