Master adding up to two 4-digit numbers with more than one exchange with this Year 4 Add up to Two 4-Digit Numbers (More than 1 Exchange) Discussion Problem. Children need to investigate which mountains George can climb to reach a target height. Calculations will require children to make more than 1 exchange.

This resource is a great extension activity that can be completed in small groups or pairs and is the perfect way to test children's understanding of making exchanges when adding with two 4-digit numbers.