Do you want some lemons???

There's a little boy, John, who wants to get 1 lemon. Someone tells him that some trader has a huge house nearby and is well known for its lemons. Our little John gets excited and starts on his journey.

When he reaches the garden, he sees that there was a path which had 3 persons guarding 3 entrances.

He reaches the first guard, who says, "I will only allow you if you give me one more than half of whatever number of lemons you bring,"

John agrees, the second and third guard present the same condition. John agrees to all.

Now, the question, How many lemons did our little John bring so that he can satisfy all the three guards and save one for himself.