SCIENTIFIC NOTATION DID YOU KNOW…….. • The distance from Earth to the North Star is about 10,000,000,000,000,000,000 meters. • The thickness of a soap bubble is 0.0000001 meter. • The United States has 12,916,000 acres reserved for state parks. MATH FOLKS CAME UP WITH A WAY TO DEAL WITH REALLY BIG NUMBERS AND REALLY LITTLE NUMBERS This method is called Scientific Notation. Using scientific notation we can write a number as the product of a power of 10 and a number greater than or equal to 1, but less than 10. THE DISTANCE FROM EARTH TO THE NORTH STAR IS ABOUT 10,000,000,000,000,000,000 METERS. 10,000,000,000,000,000,000 written out is called “standard form”. Using scientific notation, we can write the same number like this: 1.0 ´10 19 THE THICKNESS OF A SOAP BUBBLE IS ABOUT 0.0000001 METER. 0.0000001 written out is called “standard form”. Using scientific notation, we can write the same number like this: 1.0 ´10 -7 RULES FOR SCIENTIFIC NOTATION To be in proper scientific notation the number must be written with * a number between 1 and 10 * and multiplied by a power of ten 23 X 105 is not in proper scientific notation. Why? HERE’S HOW IT WORKS: 137,000,000 can be rewritten as 1.37 X 8 10 NOW YOU TRY Using scientific notation, rewrite the following numbers. 347,000. 3.47 X 105 902,000,000. 9.02 X 108 61,400. 6.14 X 104 NOW WORK BACKWARD. CONVERT THESE TO STANDARD FORM: 1.23 X 105 123,000 6 6.806 X 10 6,806,000 TRY THESE 4,000 4 X 103 2.48 X 103 2,480 6.123 X 106 6,123,000 306,000,000 3.06 X 108 WHY DOES A NEGATIVE EXPONENT GIVE US A SMALL NUMBER? 10000 = 10 x 10 x 10 x 10 = 104 1000 = 10 x 10 x 10 = 103 100 = 10 x 10 = 102 10 = 101 0 1 = 10 Do you see a pattern? NOTICE THE PATTERN = 10-1 1 10 1 100 1 1000 1 10000 = = = = 10-2 1 10 2 = 10-3 1 10 3 1 10 4 = 10-4 HERE’S HOW IT WORKS WHEN YOU HAVE A SMALL NUMBER: .0307 can be rewritten as 3.07´10 -2 YOUR TURN Using Scientific Notation, rewrite the following numbers. 0.000882 8.82 X 10-4 0.00000059 5.9 X 10-7 0.00004 4 X 10-5 MORE EXAMPLES 1) 0.0004 2) 3) 4) 5) 4 X 10-4 1.248 X 10-6 .000001248 6.123 X 10-5 .00006123 0.00000306 3.06 X 10-6 0.000892 8.92 X 10-4 HOMEWORK Page 219 1-24