The securities industry experienced dramatic growth in the last two decades of the 20th century. The following models for the industry's revenue R and expenses or costs C (both in billions of dollars) were developed as functions of the years past 1980 with data from the U.S. Securities and Exchange Commission's 2000 Annual Report (2001). and . Use the models to predict the profit for the securities industry in 2009. Round your answer to two decimal places.
A) $1.15 billion
B) $955.65 billion
C) $830.61 billion
D) $125.04 billion
E) $540.34 billion

Question

The securities industry experienced dramatic growth in the last two decades of the 20th century. The following models for the industry's revenue R and expenses or costs C (both in billions of dollars) were developed as functions of the years past 1980 with data from the U.S. Securities and Exchange Commission's 2000 Annual Report (2001).  and  . Use the models to predict the profit for the securities industry in 2009. Round your answer to two decimal places. ​
A) $1.15 billion 
B) $955.65 billion 
C) $830.61 billion 
D) $125.04 billion 
E) $540.34 billion

Quizplus · Accepted Answer

To find the profit for the securities industry in 2009, we need to subtract the expenses (costs) from the revenue.

From the given models: 
R = 0.042t^2 + 0.459t + 3.303 
C = 0.023t^2 + 0.324t + 2.205

Where t represents the number of years past 1980.

We need to find R - C when t = 29 (since we want to predict for the year 2009, which is 29 years past 1980).

R - C = (0.042t^2 + 0.459t + 3.303) - (0.023t^2 + 0.324t + 2.205)
R - C = 0.019t^2 + 0.135t + 1.098

R - C when t = 29:
R - C = 0.019(29)^2 + 0.135(29) + 1.098
R - C = 125.04 billion

Therefore, the best choice is D, $125.04 billion.

The Securities Industry Experienced Dramatic Growth in the Last Two