4-5 Compute with Scientific Notation

Transcription

1 1. About fruit flies weigh pounds. How much does one fruit fly weigh? Write in about lbs Evaluate each expression. Express the result in 2. ( ) ( ) ( ) + ( ) ( ) (24,650,000) ( ) The equatorial circumference of Earth is about kilometers. The equatorial circumference of Jupiter is about 439,263.8 kilometers. About how many times greater is Jupiter s circumference than Earth s? about 10 times greater 9. The United States has the most miles of roads in the world at about miles. Japan has about miles. How many more miles of roads does the United States have than Japan? Write in scientific notation. about mi 10. The speed of light is about miles per second. It takes about 500 seconds for light to travel from the sun to Earth. What is the approximate distance between Earth and the sun? Write in about mi Evaluate each expression. Express the result in 11. ( )( ) ( )( ) ( )(28,400) (0.042)( ) esolutions Manual - Powered by Cognero Page 1

2 ( ) + ( ) ,263,000 + ( ) ( ) ( ) ( ) 22, ( )(56,200) ( )( ) ( )( ) (0.0159)( ) The diameter of Mars is about meters. A standard table tennis ball is 0.04 meter in diameter. About how many times greater is the diameter of Mars than that of a table tennis ball? about times greater 28. The United States has a total area (including water) of about 9,826,630 square kilometers. Rhode Island is the smallest state with an area (including water) of about square kilometers. About how many times greater is the area of the United States than the area of Rhode Island? about 2500 times greater 29. The Earth is kilometers from the Sun. Mercury is kilometers from the Sun. Find the difference in distances and express your answer in km 30. Each minute, there are approximately flashes of lightning around the world. The air around a lightning bolt is heated to about degrees Fahrenheit, which is about five times hotter than the sun. Write each answer in scientific notation and in standard form. a. About how many flashes of lightning are there in a day? b. About how hot is the sun in degrees Fahrenheit? a ; 8,640,000 b ; 10,800 esolutions Manual - Powered by Cognero Page 2

3 31. A music website recently announced that over songs have been downloaded. It also announced that it has registered users. Find the average number of downloads per user and express your answer in downloads 32. Use Math Tools The table shows the weights of various marine and land animals. 34. A contractor is using a blend of two different types of sand for a new sand volleyball court. He is using cubic feet of sand that weighs 95 pounds per cubic foot and cubic feet of sand that weighs 88 pounds per cubic foot. How many tons of sand is being used for the volleyball court? 131 tons Evaluate each expression. Express the result in a. Which animal is about 10 times lighter than a right whale? b. About how many times heavier is the blue whale than the African elephant? c. Estimate the combined weight of the fin whale, right whale, and white rhinoceros. Write the combined weight in scientific notation and in standard form. a. white rhinoceros b. 20 times c ; 200, The average width of a human hair is centimeter. If the cross section of the average hair is round, use the formula A = 3.14r 2 to find the approximate area of the cross section of a hair. Write your answer in cm esolutions Manual - Powered by Cognero Page 3

4 ( ,249) ( ,000) Identify Structure Write an addition expression and a subtraction expression, each with a value of Sample answers: ( ) + ( ); ( ) ( ) 44. Which One Doesn t Belong? Identify the expression that does not belong with the other three. Explain your reasoning does not belong = , while the three remaining expressions each equal Persevere with Problems There are about red blood cells in the average adult. A googol is About how many adults would it take to have a total of 1 googol red blood cells? about adults 46. Building on the Essential Question How does writing numbers in different ways help to make it easier to compute with very large or very small numbers? Sample answer: When you compute with very large or very small numbers written in standard notation, it can be difficult to keep track of the place value. Scientific notation is a concise way of expressing very large or very small numbers, making it easier to keep track of place value when computing. 47. Ariana is evaluating ( ) + ( ), as shown below. What should Ariana have done differently to evaluate the expression correctly? made both numbers have the same A power of 10 B subtracted the exponents C multiplied 8 4 instead of adding D made the last line A 48. What is the value of ( )(1,600,000)? F G H J J esolutions Manual - Powered by Cognero Page 4

5 49. After its first year in business, a movie Web site announced that over 500,000,000 movies were downloaded by registered users. What is the average number of movies per user? A about movies B about 125 movies C movies D about 12.5 movies B 50. Short Response Earth is kilometers from the sun. Venus is 109 million kilometers from the sun. Find the difference in distances and express your answer in km Write an integer for each situation. Then identify its opposite C below zero 58; +58 or gallons per mile more than usual +15 or 15; a withdrawl of $ ; or a scuba diver's descent of 50 feet 50; +50 or 50 Complete each expression = 18 + _ _ ( 3) = = 10 _ The volume of one cube is 5 3 cubic inches. What is the volume of 3.5 of these cubes? in The speed of sound is approximately miles per hour. Write in standard form The SR-71 Blackbird is more than 30 years old. It can fly at altitudes above feet. Is it more appropriate to report the altitude as feet or as inches? ft Determine whether each equation is or false. If the equation is false, explain why ( 4) = a bank deposit of $ or 68; an airplane's ascent of 300 feet +300 or 300; false; esolutions Manual - Powered by Cognero Page 5

6 ( 3) = = 6 false; 36 (6) = ( 11) = ( 1) = 1 esolutions Manual - Powered by Cognero Page 6