MA.8.A.6.1 Use exponents and scientific notation to write large & small numbers and vice versa & to solve problems. DEFINITIONS Exponential Form: The number of times the base occurs as a factor. The number 2, is the base, and the number 3 is called the exponent. Ex. 23 = 2 x 2 x 2 Scientific Notation: a method of writing very large or very small numbers using exponents in which a number is expressed as the product of the power of 10 and number that is greater then or equal to (1) and less then 10. Ex. 7.59 x 105 = 759,000 Standard Form: EXAMPLES Example 1 Write 8.65 × 107 in standard form. 8.65 × 107 = 8.65 × 10,000,000 = 107 = 10 · 10 · 10 · 10 · 10 · 10 · 10 or 10,000,000 The decimal point moves 7 places to the right. Example 2 Write 9.2 × 10-3 in standard form. 9.2 × 10-3 = 9.2 × 0.001 The decimal point moves 3 places to the left. = Example 3 Write 76,250 in scientific notation. = 7.625 × 10,000 = 7.625 × 104 The decimal point moves 4 places. Since 76,250 is >1, the exponent is positive. Example 4 Write 0.00157 in scientific notation. = 1.57 × 0.001 = 1.57 × 10-3 The decimal point moves 3 places. Since 0.00157 is <1, the exponent is negative. 1 Computing with Scientific Notation 2 MA.8.A.6.1 Practice Problems 1. The diameter of Jupiter at its equator is approximately 143,000,000 meters. What is 143,000,000 written in scientific notation? A. 1.43 × 10-3 B. 1.43 × 106 C. 1.43 × 108 D. 1.43 × 109 2. Red tide is a high concentration of algae that can be harmful to marine animals and humans. Along the gulf coast of Florida, red tide is typically caused by the organism Karenia brevis. These organisms can be as large as 4.5 × 10-5 meters. What is 4.5 × 10-5 written in standard form? A. 4,500,000 B. 450,000 C. 0.000045 D. 0.0000045 3. The John F. Kennedy Space Center, was the site of the first space shuttle launch. Launching a shuttle requires more than one million pounds of solid propellant and 5 × 105 gallons of super-cold liquid oxygen and liquid hydrogen. What is 5 × 105 in standard form? A. 500,000 B. 100,000 C. 3,125 D. 250 5. The Earth has a diameter of about 1.27 × 104 kilometers. The dwarf planet Pluto’s diameter is estimated to be about 2.3 × 103 kilometers. About how many times larger is the diameter of Earth compared to Pluto? A. 0. 5 B. 2 C. 5 D. 10 4. What is the number 0.0004207 written in scientific notation? A. 4.207 × 104 B. 4.207 × 10-3 C. 4.207 × 10-4 D. 4.207 × 10-6 6. The table lists the populations of five countries. List the countries from least to greatest population. 7. A CD can store about 650,000,000 bytes of data. Write this number in scientific notation. Country Population South Africa 2.0 x 107 England 1.9 x 108 Japan 7.7 x 107 Spain 4.7 x 105 Germany 4.4 x 106 8. The diameter of the Sun is about 1.39 × 109 meters. Write this number in standard notation. 9. The table shows the amount of money raised by each region for cancer awareness. How much money did the North and South raise together? 10. In one week a small library checked out 1.2 x 10³ books. This is 1/5 the total number of books in the library. How many books does the library have all together? Region North South East West Amount Raised 1.46 x 104 2.38 x 104 6.75 x 103 8.65 x 103 3 11. 12. 13. 14. By studying lunar samples, scientists have learned the Moon is approximately 4,600,000,000 years old. What is this number expressed in scientific notation? 15. 16. Solve 17. Solve -4 -8 5.16 x 10 ÷ 8.65 x 10 + 9.68 x 10 4 The speed of light is about 1.86 × 105 miles per second. Write this number in standard notation. 2.775 x 10-4 – 4.775 x 104 18. 19. 4 20. 21. 5 6