LT 13.05 I can determine if a probability model is fair.
Dictionary - fair:
adjective
in accordance with the rules or standards; legitimate.
"the group has achieved fair and equal representation for all its members"
synonyms: just, equitable, honest, upright, honorable, trustworthy
adverb
without cheating or trying to achieve unjust advantage.
"no one could say he played fair"
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AA Prob Practice
Name: ________________________
5/8/15
For Exercises 1 and 2, determine whether the strategies described result in a
fair decision. Explain.
1. An art teacher wants to choose 3 of his 20 students at random to clean the
paintbrushes this week. As students arrive for class on Monday, he has them
roll a number cube. The first 3 students to roll an even number are chosen.
2. The leader of a fan club wants to choose 2 of the club’s 48 members at random
to receive a prize. The leader writes the names of the club members on slips
of paper. Then she places the slips in a box, and draws out 2 slips without
looking.
For Exercise 3, use the lines from a random number table below.
67120
61362
69656 32394
63496 65882
25564 95187
61214 47113
59758 06641
54036 04317
3. A worker at a daycare center wants to select 5 of the 42 children at random to
take on a nature walk. She assigns a two-digit number from 01 to 42 to each
child. What are the numbers of the children chosen for the nature walk?
4. A company is testing a new allergy medication. The new drug is given to 75
volunteers who suffer from allergies, and the company’s current drug is given
to 75 other volunteers who suffer from allergies. After 2 weeks, the volunteers
are surveyed about their symptoms. The contingency table shows the results.
Reported improvement
Did not report improvement
Totals
Received new drug
56
19
75
Received current drug
45
30
75
Totals
101
49
150
a. What is the probability that a volunteer reported improvement, given that
he or she received the new allergy drug?
b. What is the probability that a volunteer reported improvement, given that
he or she received the company’s current allergy drug?
c. The company decides to make and sell the new drug as an effective way to
treat allergy symptoms. Is this a good decision? Explain.
5. Three sisters are deciding which one of them will take out the
family’s recycling bin this week. Describe a way that the sisters can make a fair
decision.