Max Maths, Year 4, Learn together, Addition and subtraction with 3-digit numbers using number lines (2)

In the Max Maths Year 4 curriculum, students learn to use number lines for addition and subtraction with 3-digit numbers, employing strategies that make the calculations easier. For example, to add 257 and 199, a student can start at 257 and count on. Recognising that 199 is just 1 less than 200 simplifies the process: the student counts on 200 steps and then subtracts 1, arriving at the sum of 456. This approach turns a potentially complex addition problem into a more manageable calculation.

Subtraction is tackled with similar techniques. When subtracting 41 from 378, the student notes that 41 is 1 more than 40. By counting back 40 steps from 378 and then another 1, the student easily finds the difference to be 337. In another example, subtracting 29 from 842, the student sees that 29 is 1 less than 30. By subtracting 30 and then adding 1 back, the result is 813. Similarly, to subtract 304 from 838, the student counts back 300 steps and then 4 more, resulting in 534. These methods help students perform arithmetic operations accurately and build their confidence in handling larger numbers.