Division (3)
In the last session I took you through a few simple division sums just to get you used to the method and self-checking your work. Here's one to remind you
Here is a division sum.
Step 1 we have asked how many 3's in 3 and put the answer 1 above the 3.
Step 2 we have asked how many 3's in 9 and put the answer 3 above the nine.
There is nothing remaining so that is our answer (we think)
Step 3 we always check our work So now we multiply 13(answer) by 3 (the question).
13 X 3 = 39.
Notice how we get back to the number in the box. This means that our answer is right.
If it wasn't we should do the sum again and see how we went wrong.
Now to take you a few steps further.
Look at this example.
step 1 How many 3's in 4 (answer = 1) but there is 1 more left.
Put the one after the 4 next to the nine and then go to step 2
Step 2 How many 3's in 18 (answer = 6)
Notice how the 1 that was left over from the 4 has been put in front of the next number and then made 8 into eighteen.
Step 3 now we check
Can you remember how?
You check division by the opposite operation (multiplication)
We multiply our answer by the 3
So 3 X 16 = 48
Since 48 was what we started with our answer is correct.
Now look back through that division again making sure that you can follow each step.
Then try example 2:
Step 1 Fours into 7 = 1 remainder 3 Put the answer (1) above the 7and the remainder(3) in front of the 2
Step 2 Fours into 32= 8 no remainder. Put the eight above the 2
Step 3 self check (4 X 18 = 72) This division is correct.
How was that?
It will take some time to practise it, but you will get quicker.
Here are a few to try out. I will just put the answers and you should check your answers before to click on my check.
Questions
Don' forget to self-check before you have look at the answers!
Go to answers
Self checks:
a, 4 X 14 = 56 b,3X 27 = 81 c, 6 X 12=72
d, 4 X 24 = 96 e, 3 X 29=87
Well how did you do?
I hope you are getting used to this kind of method now.
What happens if we have a bigger number to break up (divide)?
Look at the following example:
Here we use the same method
Step 1: 4's into 5 answer 1 remainder 1
4's into 11 = 2 remainder 3 put the 2 above the 1 and the remainder 3 before the 6
4's into 36 = 9 no remainder
Step 2:
Check 4 x 129= 516. Our answer is correct.
Did you see that we just kept using the same method until we got to the end.
Before we finish for today try these last two:
DON'T FORGET TO CHECK BEFORE YOU LOOK AT THE ANSWERS!
Go to answers
4 X 197 = 197 3 X 286 = 858
Well that is enough for today. How did you find that?
You may now be getting the hang of this and want to go further.
Tomorrow we will look at fractions before we deal with remainders at the ends of these types of divisions.
Good luck
