月還款額17萬15 (180個月):
170000 * 6.80%/12 * (1+6.80%/12) 180/[(1+6.80%/12
說明:180是180的冪。
20年(240個月)月還款額1.7萬:
170000 * 6.80%/12 * (1+6.80%/12) 240/[(1+6.80%/12) 240
說明:240是240的冪。