On the above diagram, each of fifteen private colleges is represented by a circle and a dot. The light green circle, read against the green scale on the left, gives the college's annual gross tuition income in 2008; the data point is the very center of the circle. The black dot, directly above or below the center of the green circle and read against the right scale, gives the college's annual income in 2008 from investments such as endowments.

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1) For the 15 colleges shown, the graph supports which of the following statements

I. tuition income is positively correlated with student enrollment

II. investment income is negatively correlated with student enrollment

III. all colleges with over 20,000 student have less than $500 million in investment income

The options are following
A. I only
B. I and II only
C. I and III only
D. II and III only
E. I, II, and III

Show: :: Answer

B

I. tuition income is positively correlated with student enrollment
TRUE
The green dots (the college's tuition income) INCREASES as student enrollment INCREASES.

II. investment income is negatively correlated with student enrollment
TRUE
The black dots (the college's investment income) DECREASES as student enrollment INCREASES.

III. all colleges with over 20,000 student have less than $500 million in investment income
FALSE
The pair of data points 6th from the RIGHT represent a college with over 20,000 students BUT the The black dots (the college's investment income) is GREATER than $500 million

Answer:
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2) The college that is drawing the most investment income in 2008 takes in approximately how much in mean total income per student in 2008? (Total income = tuition + investments)

A) $ 5,600
B) $28,000
C) $36,000
D) $56,000
E) $237,000

Show: :: Answer

E

The college drawing the most investment income in 2008 is represented by the LEFTMOST pair of data points.
Here, the investment income is APPROXIMATELY $640 million, and the tuition income is APPROXIMATELY $180 million
So, the TOTAL income ≈ $650 million + $190 million
≈ $840 million

We can see from the diagram that there were APPROXIMATELY 4,000 students.

So, the TOTAL income per student ≈ ($840 million)/(40,00)
≈ ($840,000,000)/(4,000)
≈ ($840,000)/(4)
≈ $210,000
Answer choice E is the only answer that is close to $210,000
Answer:


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3) If the tuition income at a college exceeds its investment income, then that college is said to be "tuition driven." How many colleges shown here were tuition driven in 2008?

A) 4
B) 5
C) 6
D) 7
E) 8

Show: :: Answer

D