Today’s Maths:
Workbook: 2A
Chapter: 2 Addition and Subtraction
Lesson: 11 & 12 Subtraction with Renaming.
Links: Lesson 11 Lesson 12
Click here for a printable version of today’s blogpost: Maths Tuesday printable
Well done for all your work with column addition. Today we’re going to try with column subtraction. This is exactly the same, except we are taking away. We have to be careful that the biggest number is always on top, otherwise it won’t work.
Most of the time, it is as simple as that, but sometimes, you won’t have a bigger number on top in the ones. When this happens you will have to borrow from the 10s column – Maths No Problem call this RENAMING. When we were at school, we used Mr Ten to help us work it out.
This is Mr Ten and he is the kindest man ever! Whenever the Ones don’t have enough in their top number, they just knock on the door to see Mr Ten. The Ones say, “Please Mr Ten, we don’t have enough in our column, please can we have one of your tens?” And because Mr Ten is so kind, he always says YES! Mr Ten will give one of his tens and turn them into ones for them.
So, in the example above, the Ones only had 3 in their column, which wasn’t enough to take 6 from. So they knock knock knocked on the door and said “Please Mr Ten! Please can we have one of your tens?” Mr Ten said, “Of course you can!” Mr Ten had 5, and gave one away (so he had four left). The Ones had 3 and then a 10 from Mr Ten, and so now had 13. They can now do 13-6.
Have a go working through Lessons 11 and 12. In both lessons, the first section gets you to use circles to practise the renaming (by partitioning the number differently, e.g. 53 = 40 + 13). Look through their worked example, but if you find this too confusing, then just miss it out and practise the column method. So long as you can use column method, that’s all that matters!
*If you’re finding it tricky and want to practise simple subtraction, go back and practise Lessons 7, 8, 9 & 10 of Chapter 2. Or you could play Hit the Button subtraction games.
*If you are feeling confident with your subtraction skills, then have a go at this challenge. Although the subtraction might seem simple, I want you to focus on your explanation. Use these words to help you: ones column, tens column, same, different, changes.
Nine, nineteen and ninety
Eight, eighteen and eighty
Seven, seventeen and seventy
Six, sixteen and sixty
Five, fifteen and fifty
Four, fourteen and forty
Three, thirteen and thirty
Two, twelve and twenty
They are all the same because there are zeros in the ones column but the tens column have different numbers.
Worksheets completed
Well done for completing the MNP worksheets. Have another go at the challenge. Focus on one at a time and see if you can find the answers and then explain the pattern you see across them all.
Hi Miss,
I have finished my maths in my maths no problem workbook from school.
Bye, Bo
Well done Bo! I hope you found it okay.
All done for today. Took us awhile.
Worksheets all done.
Greetings,
Sophia
Maths completed.
Challenge question: They all have the numbers 1-8 in them. They start with different numbers and the last column has a zero at the end.
Well done Nadine, Sophia and Finley!
⭐️ A helpful hint for the challenge ⭐️
Compare them in rows:
10 – 9 = ? 20 – 19 = ?
Why do these give you the same answer?
10 – 9 = ? 100 – 9 = ?
What is the same, and what is different between these calculations?
Good luck!?
We completed all our worksheets.
Challenge
The first two columns have the same results because in the second column both numbers have 1 ten more then the first column.
10-9=1 20-19=1
the third column adds a 0 so the result has an extra 0
10-9=1 100-90=10
What a great explanation for the challenge, well done! I like how you have recognised that both numbers are 10 more in the second column than the first, and that the difference is still the same so that answers are the same. Well done!
Hello Miss,
I finished my Maths no Problem and my mum helped me with some of the questions.
Well done!
Dear Miss Carruthers,
I finished my work. I like column method best for my subtractions.
20-19 and 10-9 gives the same number because to both numbers in 20-19 we add one 10
100-9 and 10-9 give different answers because we are taking awAy the same one which is 9 but the 100 and 10 are different.
Well done Marie! I find column method the best way too – it just makes sense and helps to make the bigger numbers more manageable for me.
Dear miss Carruthers,
I have done my maths no problem for today. It was quite easy for me to do.
I completed the worksheets and it was OK.
Challenge
1. The first and second column don’t have the extra zero and gives 1 as the answer. The third column has an extra zero and gives 10 as the answer.
hi I have finished my maths, I found it ok , we only did method 2.
Joshua has completed the MNP worksheets, but found them challenging.