# How many apples should you carry? [duplicate]

This question already has an answer here:

You are on your way to your friend's house. You decide to carry 2 apples to your friend. To get to their house, you must pass across 8 gates. At each gate, the keeper will take half the amount of apples you have and return one apple back. The question is, how many apples should you carry at the beginning?

## marked as duplicate by Alconja, boboquack, Quintec, JonMark Perry, El-GuestSep 11 '18 at 1:58

• if there was a lateral thinking tag: start with zero apples, walk through the gate, throw your apple over the next gate, then you will have two apples! – Yout Ried Sep 10 '18 at 19:48
• And that's why I didn't include it, cuz I know some people have an infinitely broad imagination! – Wais Kamal Sep 10 '18 at 19:53

You need

2 apples.

This is because

Each gatekeeper will take one apple (half of two) and return one to you, meaning you keep the same number of apples through each gate.

• Haha.. Just missed it! :) – Vivek Parekh Sep 10 '18 at 15:49

I am not sure if it's this easy. But here's a try.

You need to carry only 2 Apples. At each gate, the keeper will take half the amount i.e. 1 apple and will return it. At the end, you are still left with 2 apples.

• Close one! I think I barely beat you in, but great answer nonetheless! :D – El-Guest Sep 10 '18 at 15:49
• That's correct, but @El-Guest answered first :) – Wais Kamal Sep 10 '18 at 15:49
• @El-Guest I guess yours is. – Vivek Parekh Sep 10 '18 at 15:49
• Yeah, very close :) – Wais Kamal Sep 10 '18 at 15:51

Well,

Let’s work backwards: (2 apples - 1) * 2 = 2. Therefore, you only need to bring 2 apples.

Also,

You could only bring one apple, and walk through the gates and back. Then you should have around 1.8 apples. Then leave the .8 and repeat for infinite apples! :P

• Ah, I see now. I will change my answer – Rohit Jose Sep 10 '18 at 15:46
• Nice one (never thought of this tbh)! – Wais Kamal Sep 10 '18 at 15:53
• @Wais Kamal And neither did the gatekeepers, apparently! – Rohit Jose Sep 10 '18 at 15:54