The table below shows the production of three types of cars (A, B and C) manufactured (in thousands) by an automobile company over the years.
| Year | A | B | C |
| 2012 | 1750 | 1880 | 1900 |
| 2013 | 1800 | 2950 | 2070 |
| 2014 | 2950 | 3020 | 3150 |
| 2015 | 3100 | 3240 | 3290 |
The average number of A-type cars produced by the company from 2012 to 2014 is what percent (rounded off to 1 decimal place) less than the combined average number of B-type and C-type cars produced by the company from 2013 to 2015?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 26.6%.
Average = sum of observations/Total number of observations
Total Average production of A-type cars from 2012 to 2014 = (1750 + 1800 + 2950)/3 = 6500/3 = 2166.67
Total production of B-type cars (2013 - 2015) = 2950 + 3020 + 3240 = 9210
Total production of C-type cars (2013 - 2015) = 2070 + 3150 + 3290 = 8510
Combined Average = (9210 + 8510)/6 = 17720/6 = 2953.33
Required difference = 2953.33 - 2166.67 = 786.67
⇒ Required percentage = (768.67/2953.33) × 100 = 26.6%