*I figured this was the best place to ask this question because it didn't seem to fit in any of the other categories*

Genghis Khan organized his men into groups of 10 soldiers under a “leader of 10.” Ten “leaders of 10” were under a “leader of 100.” Ten “leaders of 100” were under a “leader of 1,000.” (a) If Khan had an army of 10,000 soldiers at the lowest level, how many men in total were under him in his organization? (b) If Khan had an army of 5,763 soldiers at the lowest level, how many men in total were under him in his organization?

Assume that the groups of 10 should contain 10 if possible, but that one group at each level may need to contain fewer.

How do I go about solving this problem? For example (a) says that Khan had an army of 10,000 soldiers. So does that mean he had 10,000 men under him? Or do I add the leaders of each group so: 10 leaders of 10,000 + 10 leaders of 1,000 + 10 leaders of 100 + 10 leaders of 10 = 40 leaders (men) under him and then the same concept for (b)?