Write the recommended daily dietary intake of each nutrient in scientific notation: (a) sodium, 2,400 mg; (b) vitamin B_{12}, 0.000 006 g.
Analysis
Move the decimal point to give a number between 1 and 10. Multiply the number by 10^{x}, where x is the number of places the decimal point was moved. The exponent x is (+) when the decimal point moves to the left and (–) when it moves to the right.
Very large and very small numbers are more conveniently written in scientific notation.
| Scientifi c Notation | Number | Quantity |
| 2 × 10^{13} | 20,000,000,000,000 | Number of red blood cells |
| 6 × 10^{–6} m | 0.000 006 m | Diameter of a red blood cell |
