Please help me with the following problem:
In a stack of boards at a lumber yard, the 20th board counting from the top of the stack is immediately below the 16th board counting from the bottom of the stack. How many boards are in the stack?
I always get 36 but it should be 34?
Lumber Yard Problem
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Given,RickH wrote:Please help me with the following problem:
In a stack of boards at a lumber yard, the 20th board counting from the top of the stack is immediately below the 16th board counting from the bottom of the stack. How many boards are in the stack?
I always get 36 but it should be 34?
20th board from top = below 16th from bottom
That means 20th from the top is actually 15th from bottom.
Hence, there are 19 boards above 15th from the bottom, which is 19+15 = 34!
Hope this helps!
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1,2,3,...........18,(19/16)(20/15),14.......3,2,1RickH wrote:Would there be also a way to do it visually?
Now count them 18+1+1+14 = 34
Hope this helps!!
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From top:
1 2 3 4 ..... 18 19 20
x x x x ..... 17 16 15 ... 3 2 1 From Bottom
Total:18 (from top already counted) + 16 (from bottom already counted)= 34
or
19+15
or so on.. Just a simple counting problem. Hope that helps. Avoid drawing dots or logs Use numbers instead.
1 2 3 4 ..... 18 19 20
x x x x ..... 17 16 15 ... 3 2 1 From Bottom
Total:18 (from top already counted) + 16 (from bottom already counted)= 34
or
19+15
or so on.. Just a simple counting problem. Hope that helps. Avoid drawing dots or logs Use numbers instead.