SOLUTION: Can someone please walk me through this?
Plastic pipe is stacked so that the bottom row has 25 pipes, the next row has 24 pipes, the next row has 23 pipes, and so on until there
Algebra.Com
Question 330237: Can someone please walk me through this?
Plastic pipe is stacked so that the bottom row has 25 pipes, the next row has 24 pipes, the next row has 23 pipes, and so on until there is 1 pipe at the top of the stack. If a worker removes the top 17 rows of pipe, how many pieces of pipe will be left in the stack?
___ pieces of pipe
Thank you,
Edgar
Found 3 solutions by Fombitz, solver91311, stanbon:
Answer by Fombitz(32388) (Show Source): You can put this solution on YOUR website!
You have 25 rows of pipe.
17 rows are removed which leaves rows 18 through 25.
pieces of pipe
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!
The sum of a series of numbers is equal to the sum of the first number and the last number multiplied by the number of numbers and the product divided by 2.
For your problem, if they removed the first 17 rows of pipe, the first number in your series becomes 18. The last is 24.
n}{2}\ =\ \frac{(18\ +\ 24)\ \cdot\ 7}{2})
You can do your own arithmetic -- and you should be able to do it in your head.
John
My calculator said it, I believe it, that settles it
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Can someone please walk me through this?
Plastic pipe is stacked so that the bottom row has 25 pipes, the next row has 24 pipes, the next row has 23 pipes, and so on until there is 1 pipe at the top of the stack. If a worker removes the top 17 rows of pipe, how many pieces of pipe will be left in the stack?
___ pieces of pipe
--------------------
The total number of pipes is 1+2+3+...+23+24+25
= (25/2)(1+25) = 325
-------------------------
The top 17 rows have 1+2+3+4...+15+16+17
= (17/2)(1+17) = 153
-----------------------------
You can figure out how many are left after removing 153 of the pipes.
====================================
Cheers,
Stan H.
===================================
RELATED QUESTIONS
Log area stacked in a pile. The bottom row has 21 logs and the top row has 15 logs. Each... (answered by Alan3354)
Can someone Please help me solve this problem, Thank You very much!!!
A theater has 41 (answered by ramkikk66)
A stack of poles has 70 poles in the bottom row, 68 poles in the next row, and so on,... (answered by josgarithmetic,ikleyn)
This one would be the decay model? Can someone walk me through this, please?
In carbon (answered by ankor@dixie-net.com)
This is a problem my mom gave me and it is driving me crazy. I am in the 5th grade and... (answered by venugopalramana)
A theater has 45 seats in the first row, 49 in the second row, 53 seats in the third row... (answered by josmiceli)
Five hundred and twenty two circular cylinders are stacked in rows in
such a way that... (answered by Theo)
A display of cans on a grocery shelf consists of 20 cans on the bottom, 18 cans in the... (answered by stanbon)
Cartons are stacked in 16 rows with 4 cartons in the top row, 7in the second row, 10 in... (answered by richwmiller)