In order to perform graph analysis let’s consult the Wall Street Journal article about May’s car sales in the United States. The article analyzes sales of cars and light trucks in the U.S. retail market in May 2013. In our research we will analyze a particular graph which depicts Top 20 most popular vehicles in May 2013. The article may be retrieved from http://wap.wsj.com/mdc/public/page/2_3022-autosales.html .
Now we can discuss 2 probability problems, which may be answered from the data in the graph.
Problem 1:
If in May 2013 you picked one of the newly bought cars at random from the top 20 list, what is the probability that it would be Ford F – Series PU?
Solution:
Step1. Find the amount of Ford F-Series cars, sold in may: From the table above we know that there were 71,604 units of Ford F –Series PU sold in May 2013.
Step 2. Find total number of cars sold in May. Total number of cars sold in May is 594,825 (the sum of the sales column).
Step 3. Find the probability. To find this probability we need to divide the number of Ford F- Series PU units sold by the total number of cars sold in May 2013. Thus, the probability will be 71,604 divided by 594,825, which is 12%.
Problem 2:
If in May 2013 you picked one of the newly bought cars from the Top 20 list at random, what are the odds in favor of Toyota?
Solution:
Step 1. Find the sum of all Toyota cars in the list. There are 4 types of Toyota vehicles in the Top 20 list: Toyota Camry, Toyota Corolla/Matrix, Toyota Prius and Toyota Rav4, which were sold in the number of 39,216, 27,997, 23,522 and 20,780 units respectively. Total number of Toyota cars sold = 39,216+27,997+23,522+20,780= 111,515.
Step 2. Find total number of cars sold in May. Total number of cars sold in May is 594,825 (the sum of the sales column).
Step 3. Find the probability of picking Toyota Car. To find out the required probability we need to divide the number of Toyota cars sold by the total number of cars sold in May 2013. Total number of Thus the required probability would = 111,515/594,825 = 19%. Thus, the probability of not picking Toyota is 100%-19%=81%
Step4. Find the odds in favor of Toyota. That is the probability of picking Toyota divided by the probability of not picking Toyota, which is 19:81.
References
What’s Moving: US Auto Sales. The Wall Street Journal. (June 3, 2013). Retrieved from http://wap.wsj.com/mdc/public/page/2_3022-autosales.html
