In a certain brick wall, each row of bricks above the bottom row contains one less brick than the row just below it. If there are 5 rows in all and a total of 100 bricks in the wall, how many bricks does the bottom row contain ?  Select:
A) 18  B) 16  C) 17  D) 15  E) 19
The bottom row has x bricks   x+x-1+x-2+x-3+x-4 = 100   5x-10=100   5x=90   x= 18   18nswer:18
<result>A</result>
In a certain brick wall, each row of bricks above the bottom row contains one less brick than the row just below it. If there are 5 rows in all and a total of 100 bricks in the wall, how many bricks does the bottom row contain ?