Practice Statistics questions with worked explanations and timing guidance for Quantitative Reasoning.
The table below provides revenues of a certain company in 2002 and 2003. By what percent did the mean revenue increase from 2002 to 2003? (Express your answer as a whole number without the percent symbol.)
Correct answer: A
2002 total = 60, mean = 15, in 2003, total = 72, mean = 18, from 15 to 18, increase = 20%
Answer is 20%
During 2005, a company produced an average of 2,000 products per month. How many products will the company need to produce from 2006 through 2008 in order to increase its monthly average for the period from 2005 through 2008 by 200% over its 2005 average?
Correct answer: D
A 200% increase over 2,000 products per month would be 6,000 products per month. (Recall that 100% = 2,000, 200% = 4,000, and "200% over" means 4,000 + 2,000 = 6,000.) In order to average 6,000 products per month over the 4 year period from 2005 through 2008, the company would need to produce 6,000 products per month × 12 months × 4 years = 288,000 total products during that period. We are told that during 2005 the company averaged 2,000 products per month. Thus, it produced 2,000 × 12 = 24,000 products during 2005. This means that from 2006 to 2008, the company will need to produce an additional 264,000 products (288,000 – 24,000).
The correct answer is D.
After his first semester in college, Thomas is applying for a scholarship that has a minimum Grade Point Average (GPA) requirement of 3.5. The point values of pertinent college grades are given in the table below. If Thomas took 5 courses, each with an equal weight for GPA calculations, and received two grades of A-, one grade of B+, and one grade of B, what is the lowest grade that Thomas could receive for his fifth class to qualify for the scholarship?
$$\begin{array}{|c|c|}\hline \text{Grade} & \text{Value} \\\hline \text{A} & 4 \\\hline \text{A-} & 3.7 \\\hline \text{B+} & 3.3 \\\hline \text{B} & 3 \\\hline \text{B-} & 2.7 \\\hline \text{C+} & 2.3 \\\hline \text{C} & 2 \\\hline \text{C-} & 1.7 \\\hline\end{array}$$
Correct answer: A
Required total points = 3.5*5=17.5<br>Actual total points (4 subjects) = 2*3.7 + 3.3 + 3 = 13.7<br>Required total points for the last subject = 17.5 - 13.7 = 3.8<br>He has to get a minimum of 3.8 points or Grade A (that is 4 points). (Getting A-, 3.7 GPA, won't be enough to get an overall minimum GPA of 3.5 for the 5 subjects)<br>The correct answer is A.
A certain portfolio consisted of 5 stocks, priced at \( \$20 \), \( \$35 \), \( \$40 \), \( \$45 \), and \( \$70 \), respectively. On a given day, the price of one stock increased by \( 15\% \), while the price of another stock decreased by \( 35\% \) and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately \( 2\% \), which of the following could be the prices of the shares that remained constant?
The mean of \( (54,820)^2 \) and \( (54,822)^2 \) =