This week Room 10 is working on solving addition and subtraction problems using various strategies. A group of children worked with me on solving subtraction problems using place value partitioning as the strategy. After working for two days with class, I noticed that two-thirds of the class were able to solve subtraction problems confidently. The one-third of the class who were not very confident will work me again for two more sessions.
This is how Tayjah presented her work:
WALT: solve subtraction problems using various strategies
Problems
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strategy
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Answer
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294-167=
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294-167=
I can not subtract 7 ones from 4 ones because 7 is greater than 4, so I will borrow one ten from 9 tens and add it to 4 ones and I will have 14 ones, so 14-7=7
Since I borrowed one ten from 9 tens, I am left with 8 tens, so
80-60=20
200-100=100
So 100+20+7= 127
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=127
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2) 384-158=
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384-158=
I can not subtract 8 ones from 4 ones because 8 is greater than 4, so I borrow a 10 from the 8 and its goes down to a 7 so I add the 10 to the 4 ones and the number is 14 so I have enough to take away the 8 ones so 14-8=6
Now that I have borrowed the 10 from the 80, I am now left with 7 tens so 70-50=20
300-100=200
200+20+6=
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=226
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After doing two subtraction problems, I feel confident solving subtraction problems using place value partitioning
By Tayjah
By Tayjah
Wow, Well done Tayjah. I am so impressed by your work. It is good to see that you are able to describe how you solved the problem. Keep up with your very good work.
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