3 Jo can use either of two different routes, A or B, for her journey to school. She believes that route A has shorter journey times. She measures how long her journey takes for 17 journeys by route A and 12 journeys by route B . She ranks the 29 journeys in increasing order of time taken, and she finds that the sum of the ranks of the journeys by route B is 219 .

1. Test at the \(10 \%\) significance level whether route A has shorter journey times than route B .
2. State an assumption about the 29 journeys which is necessary for the conclusion of the test to be valid.