Question

homework #1
ec-101 hw1 pdf.pdf
student name: _________________________
passaic county community college
economics 101
professor michael c. walker
homework #1
arrange the data on the following table in meaningful order:
exam score (points) study time (hours)
70 6
10 0
90 8
30 2
50 4
point exam score (points) study time (hours)
a
b
c
d
e
the independent variable is: _________________________.
the dependent variable is: _________________________.
graph the rearranged data on the following grid:
y axis = _________
x axis = _________
according to this model, how much study time would you need to achieve a grade of 100? ______ hours.

Explanation:

Step1: Sort by Study Time

Order rows from lowest to highest study time:

Point	Exam Score (Points)	Study Time (Hours)
B	30	2
C	50	4
D	70	6
E	90	8

Step2: Identify variables

Independent variable: affects the dependent variable; here, study time controls exam score.
Dependent variable: depends on the independent variable; exam score changes with study time.

Step3: Assign graph axes

X-axis: independent variable (Study Time)
Y-axis: dependent variable (Exam Score)

Step4: Find slope of the model

Calculate rate of score change per hour:
$\text{Slope} = \frac{\Delta \text{Exam Score}}{\Delta \text{Study Time}} = \frac{90-10}{8-0} = \frac{80}{8} = 10$ points/hour
Linear model: $y = 10x + 10$ (where $y$=exam score, $x$=study time; y-intercept=10, score at 0 hours)

Step5: Solve for x when y=100

Substitute $y=100$ into the model:
$100 = 10x + 10$
$10x = 100 - 10 = 90$
$x = \frac{90}{10} = 9$

Answer:

1. Sorted Table:

Point	Exam Score (Points)	Study Time (Hours)
B	30	2
C	50	4
D	70	6
E	90	8

1. Independent variable: Study Time (Hours)
2. Dependent variable: Exam Score (Points)
3. Graph Axes:

Y axis = Exam Score (Points)
X axis = Study Time (Hours)

1. Study time for grade 100: 9 hours