1 / 29

Estimation & Graphs

Estimation & Graphs. Section 1.2. Estimation – process of arriving at an approximate answer to a question. Rounding numbers is one type of estimation. Rounding Numbers: Look at the digit to the right of the digit where rounding is to occur. Is it 5 or greater?

nevan
Download Presentation

Estimation & Graphs

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Estimation & Graphs Section 1.2

  2. Estimation – process of arriving at an approximate answer to a question Rounding numbers is one type of estimation. Rounding Numbers: • Look at the digit to the right of the digit where rounding is to occur. • Is it 5 or greater? • Yes – Add 1 to the digit to be rounded. • No – Do not change the digit to be rounded. • Replace all digits to the right with 0’s.

  3. Round 37 to the nearest ten. The symbol here means “approximately equal.” 37 ≈ 40 Rounding Numbers: • Look at the digit to the right of the digit where rounding is to occur. • Is it 5 or greater? • Yes – Add 1 to the digit to be rounded. • No – Do not change the digit to be rounded. • Replace all digits to the right with 0’s.

  4. Round 541 to the nearest hundred. 541 ≈ 500 Rounding Numbers: • Look at the digit to the right of the digit where rounding is to occur. • Is it 5 or greater? • Yes – Add 1 to the digit to be rounded. • No – Do not change the digit to be rounded. • Replace all digits to the right with 0’s.

  5. Round 16,592 to the nearest thousand. 16,592 ≈ 17,000 Rounding Numbers: • Look at the digit to the right of the digit where rounding is to occur. • Is it 5 or greater? • Yes – Add 1 to the digit to be rounded. • No – Do not change the digit to be rounded. • Replace all digits to the right with 0’s.

  6. Estimate the total cost of the purchases. $ 3 $ 2 $ 4 $ 0 $ 6 Bread $ 2.59 Detergent $ 2.17 Sandwich $ 3.65 Apple $ 0.47 Coffee $ 5.79 $ 18.67 Actual $ 15 Total Estimate Round to nearest dollar!

  7. Estimate the total cost of the purchases. $ 2 $ 1 $ 5 $ 4 $ 1 $ 2 $ 3 Soup $ 2.40 Juice $ 1.25 Roast Beef $ 4.60 Turkey $ 4.40 2 Coffees $ 1.40 Pie $ 1.85 Cake $ 2.95 $ 21.85 $ 18

  8. Estimate.

  9. Estimate.

  10. Estimate.

  11. Estimate.

  12. A carpenter earns $28 per hour. Estimate weekly salary. How many hours per week is a full-time job? Estimate annual salary. How many weeks are there in a year?

  13. Bill owes $38.50 for dinner. What is the tip? What is rounded bill? What percent should you tip? NOTE: 10% + 5% = 15% NOTE: 5% is ½ of 10%

  14. Bill owes $51.60 for dinner. What is the tip? What is rounded bill? What percent should you tip? .50

  15. Projected U.S. Population in 2050 About what percent will be of Hispanic origin? 25% Estimate the number of Hispanic people. 100,000,000 Expected population: 393,931,000 400,000,000

  16. Car Ownership in Global Perspective Estimate the number of cars per 100 people in the United States. 48

  17. Car Ownership in Global Perspective ≈ 300,000,000 Population (year 2000): 281,421,906 Estimate the number of cars in U.S. at that time. 3,000,000 × 50 300,000,000 ÷ 100 × 48 300,000,000 ÷ 100 × 50 ≈ 150,000,000

  18. Percentage of U.S. Federal Prisoners Sentenced for Drug Offenses Estimate the maximum percentage of federal prisoners sentenced for drug offenses. When did it occur? 59% in 1995

  19. Percentage of U.S. Federal Prisoners Sentenced for Drug Offenses There were 89,538 fed. prisoners in 1995. Estimate the number sentenced for drug offenses. 60% of 90,000 59% in 1995 = 54,000

  20. PROBLEM SOLVING Section 1.3

  21. FOUR STEPS IN PROBLEM SOLVING • Understand the problem. Reread if needed. • Devise a plan. • Look for patterns. • Examine graphs. • Make a list, table, or drawing if necessary. • Identify missing or extra information. • Use common sense. • Carry out the plan and solve the problem. • Check the answer.

  22. What information is missing? A man purchased five shirts, each at the same discount price. How much did he pay for them? the cost of each shirt

  23. What information is unnecessary (extra)? A roll of E-Z Wipe paper towels containing 100 sheets costs $1.38. A comparable brand, Kwik-Clean, contains five dozen sheets per roll and costs $1.23. If you need three rolls of paper towels, which brand is the better value? you need three rolls of paper towels

  24. Solve the problem. By paying $100 cash up front and the balance at $20 a week, how long will it take to pay for a bicycle costing $680? $680 - $100 = $580 balance $580  $20 = 29 weeks

  25. Solve the problem. You are an engineer and will program an automatic gate for a 50¢ toll. The gate should accept exact change only and not accept pennies. How many coin combinations must you program the gate to accept? Make a list.

  26. Solve the problem. You are an engineer and will program an automatic gate for a 50¢ toll. The gate should accept exact change only and not accept pennies. How many coin combinations must you program the gate to accept? Make a list. 11 combinations

  27. Enrico Fermi • 1901-1954 • Italian physicist • Nobel Prize in Physics in 1938 • Taught in United States after fleeing Italy • During WWII was on team of the Manhattan project • Legendary for being able to figure out things in his head

  28. Fermi Questiona question which seeks a fast, rough estimate when it is difficult or impossible to measure If everyone is standing up and no person is above another, how many students can fit into this classroom?

More Related