A child subtracted two numbers as shown below :
\begin{array}{r} 83 \ -\phantom{0}27 \ \hline 64 \end{array}
Which one of the following statements gives idea about the child's learning of subtraction?

Question

Accepted Answer

Option 1 is the correct answer because the child's error in subtraction indicates a misunderstanding of place value. In the given subtraction problem:

$$
\begin{array}{r}
  83 \
 -\phantom{0}27 \
  \hline
  64
\end{array}
$$

The child subtracted the digits in each column without considering the place value. Specifically, the child subtracted 7 from 3 in the units column, which is incorrect because 3 is less than 7. This suggests that the child did not understand the need to borrow from the tens column, which is a fundamental aspect of place value in subtraction. Instead, the child simply subtracted the smaller digit from the larger one in each column, disregarding the borrowing process.

Now, let's explain why the other options are incorrect:

2. The child does not know how to subtract: This option is incorrect because the child does demonstrate some understanding of subtraction by performing the operation in each column. The error is specific to the place value concept, not a complete lack of understanding of subtraction.

3. The child knows the process of subtraction of two-digit numbers: This option is incorrect because the child's mistake shows a lack of understanding of the borrowing process, which is crucial for correctly subtracting two-digit numbers when the top digit is smaller than the bottom digit in any column.

4. It is a mistake and it can be rectified by repeated practice: While practice can help, this option is incorrect because it does not address the root cause of the error, which is a misconception about place value. Without addressing this misconception, repeated practice alone may not lead to correct understanding.

In conclusion, Option 1 is the correct answer because the child's error specifically highlights a misunderstanding of place value in subtraction, which is a critical component of correctly performing the operation.