00:01
So a merchant bought some watches.
00:02
Let's say he bought n watches at 6 ,000 per dozen and he bought the same number, an equal number at 15 ,000 per 25 pieces so that means then that that he has n times 600 or 6 ,000 divided by 12.
00:51
So he paid plus n times 15 ,000 divided by 25, which is, let's see here, 6 ,000 divided by 12, this is 500n plus 15 ,000 divided by 25, this is 600n, which is $1100 n.
01:36
So he paid $1100 divided by 2n for 2n watches.
01:59
So that then is $550 50 per watch or a total of two watches and he sold them for 17 ,000 per 25 pieces.
02:52
So which is 680 per watch...