All of the Following Could Be Examples of Invented Strategies

question 18

Multiple Choice

All of the following could be examples of invented strategies for obtaining the sum of two-digit numbers EXCEPT:

• A)Adding on tens and then ones (For example,to solve 24 + 35,think 24 + 30 = 54 and 5 more makes 59.)
• B)Using nicer numbers to estimate (For example,to solve 24 + 47,think 24 is close to 25 and 47 is closer to 45 so 24 + 47 = 25 + 45 = 70.)
• C)Moving some to make 10 (For example,to solve 24 + 35,move 6 from 35 to make 24 + 6 and then add 30 to the remaining 29.)
• D)Adding tens and adding ones then combining (For example,to solve 24 + 35,think 20 + 30 = 50 and 4 + 5 = 9 so 50 + 9 = 59.)

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Definitions:

Intervertebral Disk

A layer of cartilage located between adjacent vertebrae in the spine, serving as a shock absorber and allowing for mobility of the spine.

Thoracic Region

The part of the body located between the neck and the abdomen, encasing the heart and lungs within the rib cage.

Vertebra

One of the individual bones that make up the vertebral column (spine) in vertebrates.

Coccyx

The small, triangular bone at the base of the spinal column in humans, commonly referred to as the tailbone.