SOLUTION: A monument is constructed by laying a row of 35 bricks at ground level. A second row, with 5 fewer bricks is centered on that; a third row with 5fewer bricks is centered on the sec

Question 841588: A monument is constructed by laying a row of 35 bricks at ground level. A second row, with 5 fewer bricks is centered on that; a third row with 5fewer bricks is centered on the second; and so on. The top row contains 10 bricks. How many bricks are there in the monument?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A monument is constructed by laying a row of 35 bricks at ground level. A second row, with 5 fewer bricks is centered on that; a third row with 5fewer bricks is centered on the second; and so on. The top row contains 10 bricks. How many bricks are there in the monument?
--------
You have an arithmetic series with a = 35 and d = -5
-----
Sum Formula::
S(n) = (n/2)(1st + last)
------
1st + last = 35+10
------
(35-10)/5 = 5 ;implies you subtracted 5 briks 5 times ;
therefore there are 6 rows
-----------
S(6) = (6/2)(45) = 3*45 = 135 bricks
================================
Cheers,
Stan H.
RELATED QUESTIONS
A pile of bricks in the bottom row, 81 bricks in the second row, 77 bricks in the third... (answered by checkley77)

A fireplace contains 46 bricks along its bottom row. If each row above decreases by 4... (answered by stanbon)

Reposted with additional: A path is to be constructed using bricks. The bricks are in... (answered by greenestamps,ikleyn)

Scott and Lauren are making a brick path in the school garden. Scott places 6 rows of... (answered by richard1234)

I need more detail solution: A child has a bag full of little toy bricks each of... (answered by kjmugno,MathTherapy,milo1954)

A path is to be constructed using bricks. The bricks are in 5 stacks of 9 bricks high, 9... (answered by Theo,greenestamps)

Re-Posted: A path is to be constructed using bricks. The bricks are in 5 stacks of 9 (answered by Edwin McCravy)

A circular garden with a radius of 8' is divided into quadrants with walkways 2' wide.... (answered by mananth,greenestamps)

A brick wall is built with bottom row having 50 bricks. Each row on top of that is one... (answered by Fombitz)