MA111 — Spring 2010January 141. Handouts: Syllabus, Worksheet 1.1, and Homework 1.1.2. Reviewed syllabus.3. Worked on question 1 of Worksheet 1.1 in groups, reporting out comments withstudent introductions.1January 191. Handouts: Homework 1.2, Worksheet 1.2.2. Reviewed answers to Homework 1.1, including some discussion on sources of dataand credibility of websites.3. Demonstrated the website WolframAlpha, http://www.wolframalpha.com .4. Collected Homework 1.1 and assigned Homework 1.2.5. Announced quiz for Thursday. Bring calculators.6. Began reviewing Introduction to Numbers and Quantities, pages 6–7. Discussedhow to make conversions by “multiplying by one.” Examples: Converting 60miles per hour to feet per second. Converting 1 trillion seconds to years.7. Looked at Worksheet 1.2, items 1, 2, and 4.2January 211. Worked on and discussed some problems for Homework 1.2.2. Reviewed some basic facts about percent.(a) 5% means5100which equals 0.05.(b) 10 is 25% of 40 means 10 = 0.25 × 40, or1040=25100.(c) Using the second expression above, you can set up and solve many typicalpercent problems.i. What is 25% of 40?x40=25100.ii. 10 is 25% of what?10x=25100.iii. 10 is what percent of 40?1040=x100.3. Quiz 1.1.4. Discussed question on percent: “Last year 50% of the members of the art clubwere men. This year 60% of the members of the art club are men. Yet there arefewer men in the art club this year than last year. How can this be?”3January 261. Passed back Homework 1.1 and Quiz 1.1.2. Collected Homework 1.2.3. Handed out Homework 1.3.4. Reviewed solutions to some of the problems in Homework 1.1. In particular,mentioned some issues regarding credibility of websites.5. Reminder: Exam #1 is on Thursday, February 4.6. Introduction to percent and percent change — See pages 22–27 of the text.(a) P % meansP100. So divide by 100 to convert a percent to decimal, and multiplyby 100 to convert a decimal to percent.(b) A is P % of N meansAN=P100. If you have two pieces of information, you canuse this to solve for the third.(c) If you increase A by P % to get B, this can be expressed as B = A(1 +P100).Using this, you can solve for B given A, and solve for A given B.(d) If you decrease A by P % to get B, this can be expressed as B = A(1 −P100).Using this, you can solve for B given A, and solve for A given B.(e) If A changes to B and you want to determine the percent change, use theformulaB−AA× 100 = P %. This works whether B is greater than A (in whichcase P is positive) or B is less than A (in which case P is negative).(f) WARNING: You cannot reverse an increase of, say, 20% by decreasing theresult by 20%. You will NOT return to the original amount.4January 281. Looked at the Street Sign and Himalayan Glaciers websites.2. Worked and extensively discussed Quiz 1.2.5February 21. Exam 1 has been moved to February 9.2. Collection of Homework 1.3 has been moved to February 4.3. Reviewed Homework 1.2 and 1.3. Some points:(a) Correct use of apostrophes in possessives.(b) Show your work — don’t just give the answer.(c) Write meaningful sentences; e.g., about ratio and percent.(d) What is $1.23 trillion divided by $100,000?(e) Think about types or categories of number misuse, not just examples.(f) Practice correct rounding.(g) There is a difference between “p e rcent of” and “percent more than”. Forexample, 300 is 150% of 200, but 300 is 50% more than 200.4. Worked on Worksheet 1.3: “Percent Change”.6February 41. Reminder that Exam 1 will be on Tuesday, February 9.2. Worked on the Exam 1 Review handout.3. Solutions to Exam 1 Review handout later posted to course website.7February 91. Exam #18February 111. Handout: Worksheet 2.1. Answered and discussed the questions.2. Handout: Quiz 2.1. Answered and submitted.3. Handout: Homework 2.1.4. Case Study 2.2 — Read and began to to answer Study Questions 1, 3, 4, and 5on page 35.9February 16 Class canceled due to weather.10February 181. Passed back Exam #1, and indicated that I plan to add 5 points to everyone’sraw exam score.2. I will send out an assignment for Homework 2.2, and also post this to the coursewebsite, later today.3. Exam #2 will be on Tuesday, March 2, with topics in percents, means and medi-ans, and introduction to indices.4. Worked on problems 1, 3, 4, and 5 on page 35.5. Looked at the government’s definition of employed, unemployed, and not in thelabor force.6. Introduced mean, median, and mode, and discussed some circumstances wheneach is helpful.11February 231. Exam #2 will be on Tuesday, March 2, with topics in percents, means and medi-ans, and introduction to indices.2. Answered questions on Homework 2.1 and collected this assignment.3. Worked on some of the problems of Homework 2.2.4. Introduced the notion of making an index from a table of values.12February 251. Reminder: Exam #2 is on Tuesday, March 2.2. Answered lingering questions on Homework 2.2.3. Collected Homework 2.2.4. Discussed handout on review questions for Exam 2.5. Began discussing Worksheet 2.2 (not on Exam #2).13March 21. Exam #214March 41. Discussed the Consumer Price Index. The value of a dollar in 2010 is not thesame as the value of a dollar in 1980. One gallon of gas cost $1.131 in January1980 and $2.731 in January 2010. Which was more expensive? The CPI allowsus to compare the value of a dollar by comparing the c ost of purchasing a certainbundle of items. In one version the index value was set to 100 in the year 1967.CPI in January 1972 = 123.2. CPI in January 1980 = 233.2. CPI in January 2009= 632.491. CPI in January 2010 = 649.098. So $649.098 [2010 dollars] = $233.2[1980 dollars] (in buying power). In 2010 dollars, the 1980 gas price becomes$3.148 [2010 dollars] per 1 [gallon of 1980 gas]. Thus gas was MORE expensivethen (what was going on in that year?). The real price has dropped by about 13percent.In 1972 the cost of tuition, room, and board at Yale for one year was $5000. In2009 it is $47,500 for the year. In 2009 dollars, the 1972 cost becomes $25669.So the real price has increased by about 85 percent, meaning it is nearly twice asexpensive as before (not 9 times as expensive).Websites: www.bls.gov/data for price data and CPI’s, andwww.bls.gov/data/inflation_calculator.htm for adjusting prices for inflation.2. Another goo d website for comparing the worth of items:www.measuringworth.com/uscompare.3. Reminder to bring Worksheet 2.2 to class next time.15March 91. Worked on Worksheet 3.1.2. Worked on questions 1–3 of