Solve the problem.
-A brick staircase has a total of 18 steps. The bottom step requires 113 bricks. Each successive step requires 4 less bricks than the prior one. How many bricks are required to build the staircase?
A) 1422 bricks
B) 1386 bricks
C) 2646 bricks
D) 2844 bricks

Question

Quizplus · Accepted Answer

The total number of bricks required is calculated using the formula for the sum of an arithmetic series. The first term (a) is 113 bricks, the common difference (d) is -4 (since each step uses 4 bricks less than the previous one), and the number of terms (n) is 18. The sum (S) of an arithmetic series is given by S = n/2 [2a + (n-1)d]. Plugging in the values, S = 18/2 [2(113) + (18-1)(-4)] = 9[226 - 68] = 9*158 = 1422 bricks.

Solve the Problem. -A Brick Staircase Has a Total of 18 Steps. the 18