10? That's Easy #2

One way to see this is this: There are six ways to place a $5×5$ square on a $10×10$ base.

There are also six ways to choose where to place it vertically.

Since both these events are independant the number of ways is $6×6= \boxed {36}$

General Form:-

The Number of $n*n$ Squares in a $k*k$ Square is

${(k-n+1)}^{2}$

Putting $n=5$ and $k=10$ , We get 36 $\ddot\smile$

Enjoy!