Show:
Vocabulary
Adding Steps
Without Regrouping
With Regrouping
Mixed Review
100
What does sum mean?
The sum is the answer to an addition problem.
100
Where do you begin adding two-digit numbers?
the ones place
100
27+11
38
100
19+57
76
100
60+21
81
200
What is an addend?
Addends are the numbers you add together to get the sum.
200
I added the ones place and the answer was 7, do I need to regroup to the tens place? Why or why not?
You do not need to regroup because the sum of the ones place is less than 10.
200
33+25
58
200
24+39
63
200
52+39
91
300
In the number 125, what number is in the ones place?
5
300
My sister added 25+25 =40. Is she correct? If not, what did she forget to do?
She is incorrect. She forgot to regroup the 1 ten when she added 5+5 =10, she just wrote the 0.
300
41+28
69
300
58+27
85
300
70+18
88
400
In the number 167, what number is in the tens place?
6
400
I added 14+16= 20. How do you know this is wrong? What steps did I miss?
I know 15 + 15 = 30, so 14 + 16 is a related fact and it must be 30 as well. You forgot to regroup the 1 ten when adding 4+6.
400
123+154
277
400
69+11
80
400
48+37
85
500
When do you need to regroup?
You must regroup when the sum of the ones place is 10 or greater.
500
If I added 59+23, would I need to regroup? If so, why?
Yes you would need to regroup because 9+3=12 which is larger than 10.
500
721+146
867
500
146+129
275
500
125+139
264