Study the line graph and answer the question that follows.
The line graph represents the number of vehicles (in thousands) manufactured by two automobile companies A and B over the years from 2010 to 2015. The X-axis represents the years and the Y - axis represents number of vehicles in thousands.
(The data shown here is only for mathematical exercise. They do not represent the actual figures of the country.)

What is the difference between the average number of vehicles (in thousands) of the companies A and B for the years 2010, 2012, 2014 and 2015?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 46.25
Average= Sum of all observations/Number of observation
The total number of vehicles of company A for years 2010, 2012, 2014 and 2015 = 260 + 224 + 266 + 348 = 1098 thousand
The average number of vehicles of company A for the years 2010, 2012, 2014, and 2015 = 1098/4 = 274.5 thousand
The total number of vehicles of company B for years 2010, 2012, 2014 and 2015 = 307 + 250 + 310 + 416 = 1283 thousand
The average number of vehicles of company B for the years 2010, 2012, 2014, and 2015 = 1283/4 = 320.75 thousand
The difference = 320.75 - 274.5 = 46.25 thousand