Mental Maths Strategies - Using what we know to help with what we don't know

Today in our Maths lesson we thought about how well we know our multiplication tables and how quickly we can recall the basic facts. We worked on a strategy that uses what we know to help with what we don't know or what we are a bit slower in computing.

Please take a look at the following example:

1. 6 x 7 = ?
2. We know 5 x 7  = 35 which is one group of seven less than 6 x 7.
3. Therefore, we take 35 and add one more group of 7 to it, which equals 42.
4. As a result, 6 x 7 = 42.
5. To further enhance our understanding, we used objects as a visual to set out the question. See the example below:

We know that 5 x 7 is 5 groups of 7 = 35

(Below is an array showing 5 x 7 = 35 + one more group of 7 = 42)       

            x x x x x     x

            x x x x x     x

            x x x x x     x

            x x x x x     x

            x x x x x     x

            x x x x x     x

            x x x x x     x

Now take a look at the students' work. Some were even taking the strategy further to complete more challenging  multiplication questions.