Multiplication and Commutative Law
When we want to multiply, we can write a number sentence like 2 x 4, and find the answer. It is commutative because we will get the same answer whether we do 2 x 4 or 4 x 2. They both have the same answer. Commutative means you can solve the calculation by swapping the two numbers and you get the same answer. You will be seeing if all your calculations for this work do this. Are they all commutative?
Watch the video and then play the fun game. When you load the game, choose x 2 table to start with and then, when you get the hang of it, try x 5 too. If you get good try x 2, x 5 and x 10!
When you answer the questions, write the calculation, draw the array and write the answer. Remember your array work from last week. It will be very useful!
Multiplication word problems
Word problems are sentences with the maths hidden within them. So you need to read the sentences and find the maths that is there. Your word problems below are all multiplication, so somewhere there will be two numbers you need to multiply to find the answer.
So you need to:
1. Read the sentences and look for the numbers.
2. Circle the numbers so you know the two numbers you need to multiply.
3. Draw the array for the multiplication calculation.
4. Count all the dots in the array and write the answer.
Dividing is sharing a number, or objects, into groups. It is important to make sure that you share equally. This means that all the groups have the same amount in. You find your answer when you count one of the groups after you have shared.
Watch the Numberblocks episode 'Block Star' and see how 12 divides (or shares) itself in different ways. This shows that numbers can be divided equally into different amounts.
For the questions help the cowboy divide his cows into pens. The fields have different amounts of cows to divide each time, so read the question carefully!
Can you solve division word problems by applying your multiplication and division skills?
Today we are going to be applying all we have learnt about multiplication and division to solve some word problems.
Remember that division is the inverse of multiplication and they both work together. If we can make connections between the numbers we can easily solve number problems.
Have a go at solving the division word problems on the sheet below.
Remember to use counters of some sort or make jottings to help you find the answer to the questions. Don’t forget to write the appropriate division calculation underneath.
SHARING WITH SPINDERELLA
Can you relate division to sharing equally?
Can you divide numbers/ sets of objects?
Look at the division symbol. Discuss what is means and words for division e.g. share, equal groups.
Explain that when something is divided up it needs to shared between a given number
Read 'Spinderella' (a story about a spider, where she is dividing up her brothers and sisters into teams). https://www.youtube.com/watch?v=Qjgp3YiaKJw
Role play Spinderella and her siblings- how would you divide a given number? Discuss strategies.
Can you write Spinderella’s problem as a division. Discuss the number sentences and the answer.
What is division?
How can you divide equally?
What do you notice about the answer?