Ralph goes to the hardware store to buy something for his house. He asks the clerk how much one will cost and the clerk looks it up and tells him it will be $3. He asks about buying twelve and is told it will be $6. Two hundred will cost $9.
What does man love more than life
Fear more than death or mortal strife
What the poor have, the rich require,
and what contented men desire,
What the miser spends and the spendthrift saves
And all men carry to their graves?
She will always need to give you 5 apples. You both need at least 5 apples to begin with, but apart from that it doesn’t matter exactly how many you each have. When she gives you 5 you will have 10 more than her because she will lose 5 and you will gain 5, resulting in a net difference of 10.
For example, if you each have 25 apples and she gives you 5 of hers, she will be left with 20 and you will now have 30, precisely 10 more than she has.