Question

Observe the number line, and select the correct option.

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• A. 6 is subtracted from 7 to get 13 as the difference.
• B. 6 is subtracted from 13 to get 7 as the difference.
• C. 6 and 7 are added to get 13 as the total.
• D. 8 is subtracted from 13 to get 7 as the difference.

Answer 1

The correct option is B 6 is subtracted from 13 to get 7 as the difference.

Say:
Let’s observe the number line to identify the option that describes it.

Steps:

• On the number line, 13 and 7 are marked.
• From 13, 3 jumps are taken backward to reach 10. 13 – 3 = 10.
• From 10, 3 more jumps are taken backward to reach 7. 10 – 3 = 7.
• In all, 6 jumps are taken backward from 13, breaking apart 6 into 3 and 3.
• We subtract 6 from 13 to get 7 as the difference.
• Hence, option C is the answer.

Q: Why do you think two jumps of 3 were taken from 13 to reach 7?
A: To find 13 – 6 using decomposition, 6 is decomposed into 3 and 3 to make ten. 3 is subtracted from 13 first, making it 10. The other 3 is then subtracted from 10 to get the answer 7.