Question 1
Ben is investigating how far people travel to work each day. He asks the people in his office how far, in miles, they travel to work each day.
The grouped frequency table gives information about their answers.
| Distance (d miles) | Frequency |
| 0 | 7 |
| 5 | 10 |
| 10 | 9 |
| 15 | 6 |
| 20 | 3 |
Calculate an estimate of the mean distance. Give your answer correct to one decimal place.
Ben finds a newspaper report that says that the average distance travelled to work each day in England and Wales in 2001 was 8.3 miles. (Source: www.telegraph.co.uk)
From this Ben concludes that the distance travelled to work each day in England and Wales has increased since 2001
(3)
Give two reasons why Ben’s conclusion may not be reliable.
(2)