The correct option is
C ![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/1578507/original_6.png)
Say: Let’s read the question and observe the given solutions in the option.
Ask:
∙ How can we subtract using the make a ten strategy?
Ans: To use the make a ten strategy to subtract, we have to first break down the smaller number such that one of the decomposed numbers when subtracted from the bigger number will make
10. Then, we subtract the other remaining decomposed number from
10 to find the answer.
∙ What is the first step to finding the difference between
14 and
7 using the make a ten strategy, and why?
Ans: We need to decompose
7 into
4 and
3 because
4, when subtracted from
14, makes
10.
∙ What do we do next?
Ans: We subtract
3, the other decomposed number, from
10 to find the answer.
∙ What is the answer?
Ans:
7
∙ Is option A the correct solution, and why?
Ans: No because in this solution,
7 is split into
4 and
3, then
4 is subtracted from
14 to make
10 but then again instead of
3,4 is subtracted from
10.
∙ Is option B the correct solution, and why?
Ans: No because in this solution,
7 is split into
5 and
2. 5 subtracted from
14 makes
9 and not
10. So in the option
10 is incorrect, thus the option is also incorrect.
∙ Is option C the correct solution, and why?
Ans: Yes because in this solution,
7 is split into
4 and
3, then
4 is subtracted from
14 to make
10. Then further,
3 is subtracted from
10 to get
7 as the answer.
∙ Is option D the correct solution, and why?
Ans: No because in this solution,
7 is split into
5 and
2.5 subtracted from
14 makes
9 and not
10. So in the option also
10 is incorrect, thus the option is also incorrect.
Hence, option C is the correct answer.
WB: Use the whiteboard to show the correct solution.
![](https://df0b18phdhzpx.cloudfront.net/ckeditor_assets/pictures/1578521/original_8.png)
Probing Question:
Q. While subtracting
7 from
14, after splitting
7 into
5 and
2, if we subtract
2 from
14 to make
12, then subtract
5 from
12 to get
7 as the answer, will this also be called a “make a ten” strategy?
A: No, because though we will get the correct answer, we are not making a ten here to subtract. So, this will not be a “make a ten” strategy to subtract.