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Peter was standing there in the farm opposite to 100 trees that stood one after the other; each 1 meter away from the next one, the first being placed 1 meter away from a hard brick wall. He was holding in his hands two identical large spherical marbles and a launcher. John, his neighbor, was passing by when he saw Peter weirded out by the normal looking trees.

-"What's with the trees, neighbor?"

-"Oh, John! It's nothing. I'm just as often trying to puzzle myself!"

-"What's in your head today?"

-"I was thinking of the most efficient method to figure out which is the closest tree from the wall, from which I should launch a marble given that the marble should not break. I have only two marbles, do you have an idea how can I do it most efficiently?"

-"Do you care if both of them break during the test?"

-"No! I just want to know THE tree!"

-"Your problem is solved!"

Devise a method in which the maximum number of tries is the least possible.

What is the maximum number of tries in this method you devised? Explain the method.

Assumptions:

1-The launcher can launch 1 marble only at a time. The launcher's power is constant and enough to make the marble hit the wall even if it was launched from the farthest tree of all.

2-The wall is unbreakable, and the marble's toughness does not change if it was not broken.

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start on tree #99 then launch from #97, #95, #93 etc. once you breack a marble back up 1 tree. example: marble breaks on tree #35, then launch at #36. Now if 2nd marble breaks at #36 then then tree is #37. And if it doesn't break at #36 then, of course, it's #36. Maximum # of launches in this method would be 51.

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What is the maximum number of tries in this method you devised? Explain the method.

14 (assuming it may not break at all, or it may break from any tree). Start from tree 87. If the marble breaks, go to #100 and work your way down until it breaks again. If it does not break at 87, repeat starting from #74, then 62, 51, 41, 32, 24, 17, 11, 6, 3.

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What is the maximum number of tries in this method you devised? Explain the method.

I think 50 .. Start with #51, breaks go to #100 and work your way down 1 at a time. Doesn`t break go to 26 and do the same

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14 (assuming it may not break at all, or it may break from any tree). Start from tree 87. If the marble breaks, go to #100 and work your way down until it breaks again. If it does not break at 87, repeat starting from #74, then 62, 51, 41, 32, 24, 17, 11, 6, 3.

Yes! that's absolutely true

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