Ordering journeys
How would you put these journey lengths in order?
Problem
Ordering Journeys printable sheet
Here are the distances (as the crow flies) in kilometres from London to various cities in the world:
Abu Dhabi 5480 Image
| Barcelona 1139 Image
| Cape Town 9680 Image
|
New Delhi 6718 Image
| Edmonton 6805 Image
| Florence 1209 Image
|
Gothenburg 1039 Image
| Houston 7812 Image
| Istanbul 2501 Image
|
Jerusalem 3611 Image
| Karachi 6314 Image
| Launceston 17425 Image
|
Put these journeys in order according to the distances involved.
Student Solutions
Well done to everybody who solved this problem. We received a lot of solutions from children telling us what the answers are, but not many solutions where children explained their thinking.
Alfie and Lily from Oakthorpe Primary in the UK explained how they approached this activity, and also thought about any difficulties they found. Alfie said:
A good way of doing this is to do biggest to smallest because it's easy to do the first 6.
One of my difficulties I encountered is when I got to under 4 (thousand) because I had already done half so I kept looking at the ones I had already done.
Good point, Alfie - it can be difficult to keep track of which numbers you've already ordered. Lily said:
My first thought was looking at the 1 thousands and then working my way up.
My difficulty was Launceston because it tricked me and I thought it was 1 thousand.
Raphæl and Mubarak from Darell Primary and Nursery School in the UK used their knowledge of where the cities were in the world to help them:
We started by finding the European cities and ordered them first. Then we looked at the remaining ones by their hundred and thousand columns and ordered them. We think that Launceston was a trick because it might look like 1,742.
Good ideas! It sounds like a few children found Launceston the most difficult to order as that distance is much greater than the other distances. I wonder how we can make sure that we're comparing digits in the same place value column when we compare large numbers?
Teachers' Resources
Why do this problem?
This challenge gives pupils experience of comparing and ordering large numbers.
Possible approach
Try to say as little as possible when introducing this task. When the group or class has finished it would be good to discuss the different approaches that pupils used.
Key questions
Tell me what you first thought would be a good way of doing this.
Tell me about any difficulties you encountered when solving this challenge.
Possible extension
Pupils could choose some other cities and investigate how far away from London they are, adding these journeys into their order. Pupils might like to first make a guess at where in the order they think the new journey will be placed before looking up the distance.
Possible support
Some pupils may need help with focusing on each particular map and the names that may be unusual for them.