Compensation
What is a strategy you can use to make adding multidigit numbers easier?
What is rounding
What is the partial sum method in addition?
Breaking down numbers by their place values and adding them separately.
What does it mean to regroup in addition?
To carry over numbers from one column to the next when a column sums to more than ten.
Sarah has 123,456 marbles, and her friend gives her 234,567 more. How many marbles does she have now?
358,023 marbles
If you have 238,456 + 100,244, what number can you round to make addition easier?
What is 100,244
100,244 - 244 = 100,000
Find the partial sums for 123,456 + 234,542.
100,000 + 200,000 = 300,000
20,000 + 30,000 = 50,000
3,000 + 4,000 = 7,000
400 + 500 = 900
50 + 40 = 90
6 + 2 = 8
357,998
Add 456,789 + 345,678 using regrouping. What is the answer?
802,467
Explain how you can use compensation to add 345,678 + 1,234.
Round 345,678 to 345,680 and 1,234 to 1,230; add 345,680 + 1,230 = 346,910.
*Answer may vary*
How do you calculate the partial sums for 456,225 + 123,321?
400,000 +100,000 = 500,000
50,000 + 20,000 = 70,000
6,000 + 3,000 = 9,000
200 + 300 = 500
20 + 20 = 40
1+5 = 6
579,546
What place value do you regroup when adding 587,654 + 123,345?
If a factory produced 678,910 toys last month and 123,456 toys this month, how many more toys did they produce last month than this month?
555,454 more toys
Use compensation to estimate the sum of 587,230 + 412,890. What is the estimated sum?
About 1,000,000
Show the partial sums for 678,110 + 121,456.
600,000 + 100,000 = 700,000
70,000 + 20,000 = 90,000
8,000 + 1,000 = 9,000
100 + 400 = 500
10 + 50 = 60
0 + 6 = 6
799,566
Solve 678,910 - 305,078 using regrouping.
373,832
If you want to add 299,999 + 700,001 using compensation, what numbers would you round?
Round 299,999 to 300,000 and 700,001 to 700,000; add 300,000 + 700,000 = 1,000,000.
Use the partial sum method to add 234,567 + 765,432. What is the total?
999,999