Addition and Subtraction

Lesson

There are many ways to tackle addition problems, so having a few to choose from means we can pick the one prefer. Sometimes, the type of problem means one method is much more suitable.

Let's start by adding only two numbers together. We can look for patterns in addition, use a place value table, use a vertical algorithm, and even partition our numbers. In video 1, we work through some examples, and place value turns out to be very useful. We even use the *bridge to $10$10* strategy in one problem. Then we'll solve one problem three different ways!

Evaluate $786+692$786+692

In Video 2, we're going to think about how to choose a strategy that works best for addition problems. When it comes to adding several numbers together, writing the problem in a vertical algorithm, or down the page, is ideal. Let's work through one of these, and then perform a quick check, to see if our answer seems reasonable.

Remember!

There are many ways to solve addition problems, so remember to think of place value, partitioning numbers, bridging to 10, and any patterns that exist.

Evaluate $563+771+439$563+771+439

$\editable{}$ $\editable{}$ $\editable{}$ $5$5 $6$6 $3$3 + $7$7 $7$7 $1$1 + $4$4 $3$3 $9$9 $\editable{}$ $\editable{}$ $\editable{}$ $\editable{}$

Evaluate $15+6236+973+8428$15+6236+973+8428.

Use a range of additive and simple multiplicative strategies with whole numbers, fractions, decimals, and percentages.

Record and interpret additive and simple multiplicative strategies, using words, diagrams, and symbols, with an understanding of equality