Economics 2122 A
Assignment 1
Answer Key
Question 1.69
Cross table and bar chart of drink preference vs. type of vehicle
Vehicle
Pickup
Car
Subtotal
Beer
71
32
103
Wine
29
68
97
Subtotal
100
100
200
Question 2.7
Find the measures of central tendency for t
Assignment 2
Answer Key
Question 3.67
Let G good part, D defective part
a)
b)
c)
d)
e)
f)
P(D) = .1
P(B) = .35
P(D|B) = P(B D)/P(B) = .05/.35 = .1429
P(B|D) = P(B D)/P(D) = .05/.1 = .5
No, since P(GB) which is .3 P(G)P(B) which is .315
P(G|A) = .27/.29 =
Economics 2122 A
Assignment 4
Answer Key
Question 2.51
In one year, growth of 500 largest U.S. corporations had a mean of 9.2%, standard deviation of 3.5%.
a. Find the range in which it can be guaranteed that 84% of the growth figures lie.
Use Chebyshevs
Economics 2122 A
Assignment 5
Answer Key
Question 8.7
Using independent random samples, find a 95% confidence interval estimate of the difference in the means of
the two populations
( x y ) z / 2
2
25 14
x2 y
= (140 120) 1.96
= 20 1.3128, or (18.6872, 21