Would you rather….

Would you rather…. Have 50 acre crop planted with seeds that carry a 38% survival rate Have a 30 acre crop planted with seeds the carry a 58% survival rate

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YOU MAY USE YOUR CALCULATOR, NOTES, AND THE BOOK TO ASSIST YOU • SHOW ALL WORK AS YOU GO • MARK PROBLEMS THAT WERE MOST CHALLENGING FOR YOU • GO BACK AND STUDY THOSE PROBLEMS TONIGHT 6.1-6.4 Jeopardy!

6.1 $100

6.1 $100 answer Set up proportion Always out of 100% Use cross products 300 = 8X Divide by 8 Answer: 37.5%

6.1 $200 20% as a fraction

6.1 $200, answer We know the total is always out of 100%. Simplify. Divide by 20/ 20 20/20 is the same as one whole

6.1 $300 Convert the fraction to a decimal 37

6.1 $300, answer The − sign means divide Round to the nearest hundreth or thousandth 37 3 ÷ 7 = Answer: .43 or .429

6.1 $400 Put in order from least to greatest: 245%, ⅘, 66%, .133

6.1 $400, answer Choose one form to put all the number in. I chose percents since there are already 2 of them. Use proportions and cross products. ⅘= 80% .133 = 13.3% Decimal % Multiply by 100

6.1 $500 About 342,000 km2 of Greenland’s total area (2,175,000 km2) is not covered with ice. To the nearest percent, what percent of Greenland’s total area is not covered with ice?

6.1 $500, answer Write and label a proportion. The total is always out of 100%. 342,000 (100) = 2,175,000x Use cross products to solve Answer: 16%

6.2 $100 Shannon’s printing company has determined that approximately 6% of the books it prints have errors. Out of a printing run of 2050 books, Lexi, the production manager estimates that 250 books have errors. Estimate to see if Lexi’s number is reasonable. Explain.

6.2 $100, answer 6%  2050 ≈ 5%  2000 Estimate and use easy numbers. ≈ 0.05  2000 Write 5% as a decimal. ≈ 100 Multiply. Answer: Lexi’s number is not reasonable. Only about 100 books have errors. 250 is much greater than 100.

6.2 $200 Estimate: 113% of 80

6.2 $200, answer 113% ≈110% Estimate 113% 113% is close to 110% Break into %’s you can calculate mentally: 100% + 10% 100% of 80 = 80 10% of 80 = 8 Answer: 80 + 8 = 88

6.2 $300 Estimate: 34% of 12

6.2 $300,answer ⅓of 12 What is 34% close to? 34% ≈ 33⅓ % 33⅓% = ⅓ Answer: 4

6.2 $400 Ian had dinner with some friends at a restaurant. The check for his dinner was $10.25. If he wants to leave close to a 20% tip, about amount Ian should pay?

6.2 $400, answer Break down 20% to easier %’s 10% + 10% = 20% 10% of $10.25 ≈$1 Another 10% ≈ $1 $10.25 + $1 + $1= Possible answer: $12.25 Add the price of food + tip

6.2 $500 Approximately 8% of each batch of jeans produced at Jack’s factory is defective. Rishi said that in a batch of 400 jeans, about 35 jeans would be defective. Estimate to determine if his number is reasonable. Explain.

6.2 $500, answer 8% ≈ 10% 10% of 400 = 40 40 ≈ 35 Round 8% to 10% Calculate 10% of 400 Compare to 35 Yes, because 8% of 400 is a little less than 10% of 400. 10% of 400 is 40, and 35 is a little less than 40.

6.3 $100 What percent of 33 is 22?

6.3 $100, answer Set up proportion Use cross products to solve Divide by 33 (100) = 33 X Answer: 66⅔ %

6.3 $200 Of Earth’s 197 million mi2 of surface area, about 139 million mi2 is water. Find the percent of Earth’s surface that is covered by water.

6.3 $200, answer Set up proportion Use cross products to solve Divide by l97 to isolate x 139 million (100) = 197 million (x) Answer: 70.6%

6.3 $300 Four friends volunteered to cut the grass around their neighbor’s house. Naja cut 23% of the grass, Diego cut 1/5 of the grass, Michael cut 0.31 of the grass, and Max cut the rest. What percent of the grass did Max cut?

6.3 $300, answer 100% -23% - 20% -31% = X 100%-74%= X 26% = x

6.3 $400 Irie organizes her music collection by genre. ½ of her collection is rock, 0.125 is pop, 6% is classical, 9.5% is country, and the rest of her collection are jazz. What percent of her CD collection is jazz?

6.3 $400, answer Convert all amounts to % Add up all % and subtract from 100% Answer: 22% jazz

6.3 $500 After a drought, a river had only 50⅔ % of the average amount of water flow. If the average amount of water flow is 60,000,000 gallons per day, how much water was flowing in the river after the drought?

6.3 $500, Answer • Set up proportion. • Convert 50⅔ % to a decimal • ⅔ ≈ .666666 ≈.67 • 50⅔ % ≈ 50.67 • Use Cross Products to Solve • Divide by 100 • Answer: 30,400,200 gallons of water after the drought

6.4 $100 Sophie earned 95% on a test by answering 19 questions correctly. If each question was worth the same amount, how many questions were on the test?

6.4 $100, Answer • Set up proportion • Use cross products to solve • Divide by 85% to isolate x Answer: 20

6.4 $200 When a giraffe is born, it is approximately 55% as tall as it will be as an adult. If a baby giraffe is 5.2 feet tall when it is born, how tall will it be when it is full grown, to the nearest tenth of a foot?

6.4 $200, Answer • Set up proportion • Use cross products to solve • Divide by 55% to isolate X • Round to nearest tenth Answer: 9.5 feet

6.4 $300 Jayden and Nate caught a fish that weighed 15.5 lb. This was 85% of the weight of the largest fish that they had ever caught. What was the weight, to the nearest tenth of a pound, of the largest fish that Jayden and Nate had ever caught?

6.4 $300, Answer • Set up proportion • Use cross products to solve • Divide by 85% to isolate X • Round to nearest tenth Answer: 18.2 pounds

6.4 $400 Tiffany read 4novels written by Veronica Roth. This represents 20% of the books she read this school year. How many books did Tiffany read in all?

6.4 $400, Answer • Set up proportion • Use cross products to solve • Divide by 20% to isolate X Answer: 20 books read

6.4 $500 60 is 12% of what number?

6.4 $500, Answer • Set up proportion • Use cross products to solve • Divide by 12% to isolate X Answer: 500

Would you rather….

Would you rather….

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