Errata for Math in Society

Errata and Changes for Math in Society

Apportionment

  • Just before the section on Hamilton's Method, it says "We will look at four ways of solving the apportionment problem. Three of them..."

Changes Made Edition 2.5 -> 2.6

Probability

  • Solution to Try it Now 3 is incorrect: P(at least one is white) = 1 - P(neither is white) = 1 - P(not white socks AND not white tee) = `1 - 4/10*4/7 = 1 - 16/70 = 54/70 = 27/35 ~~ 77.1%` 
  • Solution to Try it Now 9 is incorrect: the numerator should be 10*4=40

Describing Data

  • The solution to exercise 7a is incorrect; the data is listed wrong.  

Voting Theory

  • Exercise 21 should be reworded to clarify that it's asking about voting insincerely so their preferred candidate will win

Changes Made Edition 2.4 -> 2.5

Added Logic chapter

Corrected these typos/errors:

Weighted Voting

  • Try it Now 2: The answer for the quota of 16 is wrong. The answer is correct for a quota of 15.  For a quota of 16, all three players have veto power.
  • Try it Now 4: Between the list of coalitions and the table, the sentence should read: P1 is pivotal 3 times, P2 is pivotal 3 time, and P3 is pivotal 0 times.

Finance

  • Example 14: The remaining balance after 5 years should be $162,758, resulting in $34,292.80 to interest.
  • Exercise 15: The answer for part a should be $320,243.29.

Probability

  • Example 17, the final calculation should be `1/102 + 1/102 = 2/102 = 1/51` 

Sets

  • Exercise 12 should be `C subset U` , not `C subset D` 

Historical Counting

  • Exercise 1: The answer is incorrect; the 3 jars in the middle should be x3, making the total count 36.
  • Exercise 33, 35: The problem was represented in dots using base 10 rather than base 20.

Cryptography

  • Exercise 1: The list of letters above the question didn't include W
  • Exercise 9: The answer should be MNI YNE TBA AEH RTA TEA TAI LRE A

Changes made 2.3 -> 2.4

Problem solving

  • In Unit conversions, added a note that fluid ounces are a capacity measurement, and should not be used as a weight measurement.
  • Info for meatloaf problem: Clarified that 15ounces is a net weight.

Apportionment

  • In Alabama Paradox, corrected "Maine" to "Rhode Island"
  • In New States Paradox, corrected by swapping "New York" and "Maine"

Graph Theory

  • In Example #1, added labels to the vertices
  • Clarified definition of vertex
  • #22: Clarified distances were in kilometers

Scheduling

  • #27: Fixed lettering
  • Added new questions, 29-37

Finance

  • #1: Inserted "one-time" with the interest rate
  • #4: Inserted "annual" with the interest rate

Statistics

  • Clarified the definition of simple random sample to say "every member of the population and any group of members has an equal probability"

Sets

  • #43: Should say "and" instead of "or"

Solutions:

  • Growth Models #7c: The answer was missing a 7; should be 794,061
  • Probability #7: The answer should be 1/5! = 1/(5P5) = 1/120.