Compensation Strategy Addition: Friendly Decade NumbersFREEWorksheet Generator(Grade 2)
Compensation Strategy Addition: Friendly Decade Numbers worksheets (Grade 2) with step-by-step answer keys. Generate unlimited unique practice sheets.
Mastering Compensation Strategy Addition: Friendly Decade Numbers: Core Concepts & Mental Models
The compensation strategy transforms tricky multi-digit addition problems into friendly, instant mental math calculations. When an addend is close to a multiple of 10 (such as 39 or 48), students add a small number (+1 or +2) to round it up to the friendly decade, and subtract that exact same amount (-1 or -2) from the other addend. Because what is given to one side is taken from the other, the total sum is preserved [(A + k) + (B - k) = A + B].
๐ก Essential Strategies for Compensation Strategy Addition: Friendly Decade Numbers
๐ฏ Spot the Near-Decade Number
Look for numbers ending in 7, 8, or 9 (e.g., 38, 49, 57) that are only 1, 2, or 3 away from the next multiple of 10.
โ Round Up to the Friendly Decade (+k)
Add 1, 2, or 3 to reach the nearest ten (e.g., 38 + 2 = 40; 49 + 1 = 50).
โ Balance by Subtracting from the Other Addend (-k)
Subtract that identical adjustment from the second addend (e.g., 25 - 2 = 23; 36 - 1 = 35).
โก Add the Friendly Numbers Mentally
Add the friendly tens number to the compensated number: 40 + 23 = 63, or 50 + 35 = 85. No regrouping or paper pencil carrying required!
๐ Key Mathematical Vocabulary
Compensation
A mental math strategy where you adjust one number to make it easier to work with, and make the opposite adjustment to the other number to keep the balance.
Friendly Number (Decade Number)
A multiple of 10 (like 20, 30, 40, 50, 60, 70, 80, 90, 100) that ends in zero and is easy to compute mentally.
Adjustment (k)
The small amount (typically 1, 2, or 3) added to one addend and subtracted from the other.
Addend
Any of the numbers that are added together to find a sum.
โ Frequently Asked Questions
How do you solve a compensation strategy addition: friendly decade numbers problem step by step?
Here is a worked example: "Use the compensation strategy to solve: 38 + 25.". Solution: 1. 38 is close to 40 (+2). 2. Take 2 away from 25: 25 - 2 = 23. 3. Friendly equation: 40 + 23 = 63. Therefore, 38 + 25 = 63. โ
What is the core learning objective for compensation strategy addition: friendly decade numbers?
Fluently add within 100 using mental math compensation strategies; adjust one addend to the nearest friendly decade (multiple of 10) by adding k, and compensate by subtracting k from the other addend [(A + k) + (B - k) = A + B]. This directly aligns with Common Core Standard CCSS.MATH.CONTENT.2.NBT.B.5.
How does the unlimited compensation strategy addition: friendly decade numbers worksheet generator work?
Every click of 'Generate New Worksheet' creates a completely fresh set of compensation strategy addition: friendly decade numbers problems with unique numbers. No two worksheets are ever the same โ perfect for daily practice, homework variety, and preventing student copying. You can also customize the problem count (6, 8, 10, 12, 15, or 20 problems per sheet).
Are these compensation strategy addition: friendly decade numbers worksheets free to print with answer keys?
Yes! Every single worksheet on PanMaths is 100% free with no sign-up needed. Each sheet includes a dedicated Answer Key on Page 2 with step-by-step intermediate evaluation lines for 1-minute grading.