10ticks Daily Puzzle

A Pound of Oranges
Two market traders were selling oranges. One was selling 30 oranges for Ł1, whilst the other offered 20 for Ł1. One afternoon they were both called away, and each had 300 oranges unsold. These were handed to a friend to sell at 50 for Ł2. It will be seen that if they had sold there oranges seperatley, they would have made Ł25, but when they were sold together, they fetched only Ł24. So what happened to the missing Ł1? surely, 30 for Ł1 and 20 for Ł1 is the same as 50 for Ł2, isn't it?

A Pound of Oranges

Two market traders were selling oranges. One was selling 30 oranges for Ł1, whilst the other offered 20 for Ł1. One afternoon they were both called away, and each had 300 oranges unsold. These were handed to a friend to sell at 50 for Ł2. It will be seen that if they had sold there oranges seperatley, they would have made Ł25, but when they were sold together, they fetched only Ł24.
So what happened to the missing Ł1? surely, 30 for Ł1 and 20 for Ł1 is the same as 50 for Ł2, isn't it?

Solution
The two ways of selling are only identical when the number of oranges sold at 30 for Ł1 and 20 for Ł1 is in the proportion 30 to 20.