Question

Three hundred sixty bricks are stacked, 30 bricks in the bottom row, 29 in the next row, 28 above that and so on. In how many rows are the 360 bricks placed and how many bricks are there in the top row?

Answer 1

Answer:

a)360 blocks are placed in $n=16$ rows

b)There are $15bricks$ in the top row.

Explanation:

From the question, we can deducted that there is decrease in the number of rows by 1 from 30 to some number of rows .

Let denote the number of rows as 'n'

Given:

Sn = 360

a = 30

d = -1.

To calculate Sn, we will make use of formula below;

Sn = n/2 (2a + (n - 1)d )

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