Indd s 26 s 26 41012 340 pm 41012 340 pm solution

KrugWellsECPS3e_Micro_CH02A.indd S-26 4/10/12 3:40 PM 4/10/12 3:40 PM

5.
For each of the accompanying diagrams, calculate the area of the shaded right
triangle.
1
5
4
3
2
1
2 3 4 x
y
5
100
80
60
40
20
10 15 20 25 x
y
10
50
40
30
20
10
20 30 40 50 x
y
1 0 0
0 0
10
8
6
4
2
2 3 4 5 x
y
Panel (a)
Panel (b)
Panel (c) Panel (d)
× 4
× 10
× 40
× 4
6.
The base of a right triangle is 10, and its area is 20. What is the height of this right
triangle?
CHAPTER 2 APPENDIX GRAPHS IN ECONOMICS
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Solution
7.
The accompanying table shows the relationship between workers’ hours of work per
week and their hourly wage rate. Apart from the fact that they receive a different hour-
ly wage rate and work different hours, these five workers are otherwise identical.
a. Which variable is the independent variable? Which is the dependent variable?
b. Draw a scatter diagram illustrating this relationship. Draw a (nonlinear) curve
that connects the points. Put the hourly wage rate on the vertical axis.
c. As the wage rate increases from $15 to $30, how does the number of hours
worked respond according to the relationship depicted here? What is the average
slope of the curve between Athena’s and Boris’s data points using the arc method?
d. As the wage rate increases from $60 to $75, how does the number of hours
worked respond according to the relationship depicted here? What is the average
slope of the curve between Diego’s and Emily’s data points using the arc method?
7.
a. If the wage rate is greater than your opportunity cost of time, you will choose
to work. So the wage rate is the independent variable and the number of hours
worked is the dependent variable.
b. The accompanying diagram illustrates the relationship between the hourly wage
rate and the number of hours worked. Since the hourly wage rate is the price paid
for labor, economists place wages on the vertical axis—just as in the case of other
types of prices.
$75
60
45
30
15
0
Wage rate
(per hour)
Quantity of labor (hours per week)
28 29 30 31 32 33 34 35 36 37