The segment that joins the midpoints of two sides of a triangle is parallel to the third side and half the length of the third side.
Each side of triangle MNK has as endpoints two midpoints of sides of triangle ABC, so each side of triangle MNK is half the length of a side of triangle ABC.
The payment would be $198.01 and the total interest would be $1,880.75. Pretty straightforward with a financial calc. I can show you the keystrokes if you want, just message.
