Number (place value): Salmon Migration
The Problem
A team of scientists wanted to know how far some Atlantic salmon had travelled from the sea to their spawning ground in the upper reaches of the River Wye. To do this, they fixed electronic tracking tags to 5 salmon. You can see the salmon (fishes A – E) in the picture opposite. They have been ordered according to the distance that they swam. Salmon A swam the shortest distance and salmon E swam the furthest. All of the salmon swam a distance that was greater than 2,000 km and less than 5,000 km.
Can you suggest the distance that each fish swam using the two sets of digit cards (0 – 9)? You can only use each digit card once.
Is there more than one solution to this problem? How do you know?
Did you know?
By tagging fish, scientists can better understand the migration patterns and feeding habits of a particular fish species. This is especially important now that many species are facing an uncertain future due to climate change and over fishing.
Visualising the Problem and Getting Started
Zaynab said, “The shortest distance that salmon A could have swum is 2,001 km.”
Do you agree with Zaynab? How do you know?
Max said, “The greatest distance that salmon E could have swum is 4,999 km.”
Do you agree with Max? How do you know? 