Two-Digit Subtraction: Solving 53 - 38 Using Block Decomposition

Let's solve the subtraction problem to find out how many blocks remain:

Given:

• Total number of blocks = $53$
• Number of blocks removed = $38$

We need to perform the subtraction of $38$ from $53$:

Set up the subtraction column:

• $\begin{array}{c} \phantom{-} 5\phantom{8} \\ - \, 3\phantom{5} \\ \hline \end{array}$ Tens digit (5) minus 3 is 2.
• $\begin{array}{c} \phantom{2}3 \\ - \phantom{3}8 \\ \hline \end{array}$ Units column requires borrowing: change $5$ tens to $4$ tens and add 10 to units.
• $\begin{array}{c} \phantom{1}13 \\ - \phantom{1}8 \\ \hline \phantom{1}5 \end{array}$

Final calculation gives $15$.

Therefore, the number of blocks remaining is $15$.