Question

I need help solving the following problem:There are 56 concrete blocks available to make a retaining wall. The bottom three rows will all have the same number of blocks. The next six rows will each have two blocks fewer than the road below it. How many blocks are in each row?

Answer 1

In total we have 9 rows.

Three rows have x blocks, and each of the following row has 2 blocks fewer than the previous row.

Since there are 156 blocks in total, we can write the equation:

$\begin{gathered} x+x+x+(x-2)+(x-4)+(x-6)+(x-8)+(x-10)+(x-12)=56 \\ 9x-42=156 \\ 9x=198 \\ x=\frac{198}{9} \\ x=22 \end{gathered}$

So the number of blocks in each row is:

22, 22, 22, 20, 18, 16, 14, 12, 10.