1. Computing with Scientific Notation Module 6, Lesson 6 Online Algebra VHS@PWCS

2. Exponent Refresher! Any time you need an exponent refresher, click on the following link. You will find it on every page.

3. There are an average of 25 billion red blood cells in the human body and about 270 million hemoglobin molecules in each red blood cell. What is the average number of hemoglobin molecules in the human body? To solve this problem we must multiply. 25 billion by 270 million. 25,000,000,000(270,000,000) That is a lot of zeros to deal with!

4. 25,000,000,000 x 270,000,000 Using scientific notation and the rules of exponents makes this easier. 1. Write each number in scientific notation. (2.5 x 10 10 )(2.7 x 10 8 ) 2. The commutative property lets us regroup. (2.5)(2.7) x (10 10 )(10 8 ) 3. Multiply. 6.75 x 10 18

5. Try these! (6.4 x 10 3 )(7 x 10 2 ) 1. Regroup (6.4)(7) x (10 3 )(10 2 ) 2. Multiply 44.8 x 10 5 3. Since 44.8 is not between 1 and 10, we need to move the decimal, one further away and change the exponent. 44.8 x 10 6 (4 x 10 2 )(15 x 10 -6 ) 1. Regroup (4)(15) x (10 2 )(10 -6 ) 2. Multiply 60 x 10 -4 3. Make sure the number is in scientific notation. 6 x 10 -3

6. Taking a number in scientific notation to a power. (2 x 10 7 ) 3 1. Follow the rules for taking a power to a power. Take everything in the parentheses to the third power. 2 3 x 10 7(3) 8 x 10 21

7. Now you try (1.2 x 10 -5 ) 4 1. Take everything to the 4 th power. 1.2 4 x 10 -5(4) 2. Simplify 2.0736 x 10 -20 (4 x 10 6 ) -3 1. Take everything to the –3 power. 4 -3 x 10 6(-3) 2. Simplify 0.015625 x 10 -18 3. Make sure it is in scientific notation. 1.5625 x 10 -16

8. Scientific Notation and Division 1. Just divide the decimal by the decimal and the power of 10 by the power of 10.

9. Try these! 1. Regroup 2. Divide 4 x 10 7 1. Regroup 2. Divide 0.65 x 10 -5 3. Write in Scientific notation. 6.5 x 10 -6

10. Exponent Refresher!  Multiplication Property – just add the exponents. (x 10 )(x 12 ) X 10 + 12 X 22  Powers To a Power – multiply the exponents (c 4 ) 6 c 4(6) c 24  Division Property – subtract the exponents and put the variable where the largest exponent was.