Two women were selling peppers, one at 3 peppers for a dollar and the other at 2 peppers for a dollar.   One day, they were both called away, so they left their peppers with a friend.

To simplify the reckoning, the friend combined the two stocks (there were 30 of each) and sold them all at 5 for two dollars.   So, she took in 24 dollars.

When it came to dividing the proceeds between the owners, trouble arose.   The one who had 30 peppers at 3 for a dollar wanted $10.   The other who had 30 peppers at 2 for a dollar wanted $15.   That makes $25.   But the friend only had $24.

So, the friend was a dollar short.   What happened to the dollar?

The ratio of 3:2 must be maintained.
The sale of 60 peppers would have come out alright if there had been 36 of the cheaper ones and 24 of the more expensive ones.   But with 30 of each, 6 of the better peppers were sold at the cheaper rate.