Mary splits an equilateral triangle into smaller triangles and color-codes them, as shown in the figure below. The first time, she makes 3 white triangles and 1 black triangle. The second time, she makes 6 white triangles and 3 black triangles. The third time, she makes 10 white triangles and 6 black triangles. She continues this process.

How many black triangles does she make the tenth time?

How many black triangles does she make the twentieth time?