Column subtraction 4: Lesson 3: walruses
Spot the Mistake!
Someone has made a mistake in their column subtraction. Can you explain the mistake to your talk partner?
![](https://www.naturalcurriculum.co.uk/app/uploads/2021/07/Picture2-9.png)
Did you know?
Walruses have few natural predators, although polar bears and killer whales are known to occasionally attack them. However, even an injured walrus is a formidable opponent for a polar bear, and direct attacks are rare.
Use PAWS, counters and column subtraction to solve the following word problem.
A brave polar bear charged at a colony of 2,604 basking female walruses. During the attack, 1,316 walruses retreated to the relative safety of the water, while the remaining walruses stayed on land and formed a barrier of blubber around their calves.
How many walruses remained on land in the polar bear attack?