Lumber Yard Problem

[RickH]

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?

[thirst4edu]

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?

Given,
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!

[RickH]

Thanks, now I see. It's always these kinds of problems that just mess up my Quant score

[Mayur Sand]

Iam still not clear on this problem . can some one explain in more detail

[RickH]

Would there be also a way to do it visually?

[kvcpk]

Would there be also a way to do it visually?

1,2,3,...........18,(19/16)(20/15),14.......3,2,1

Now count them 18+1+1+14 = 34

Hope this helps!!

[Makushr1]

I did it real quick by making dots on a piece of paper representing the lumber. Did 20 going down then went back up. Just make sure u read it carefully since the 20th is BELOW the 16th.

[anantbhatia]

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.