Question

people in book club
90
85
80
75
70
65
60
number of people in
the book club
1 3 5
number of weeks
how many people
were in the book
club after
4 weeks?
about 63 about 80

Explanation:

Step1: Identify known points

Points: (1, 64), (3, 73), (5, 84)

Step2: Calculate weekly growth rate

Growth from week1 to 3: $\frac{73-64}{3-1} = \frac{9}{2} = 4.5$ people/week

Step3: Find week4 population

Week3 population + 4.5 = $73 + 4.5 = 77.5 \approx 80$

Answer:

B. About 80