enigma123 wrote:
In a certain conference room each row of chairs has the same number of chairs, and the number of rows is 1 less than the number of chairs in a row. How many chairs are in a row?
(1) There is a total of 72 chairs.
(2) After 1 chair is removed from the last row, there is a total of 17 chairs in the last 2 rows.
Any idea how the answer would be D?
Given: Number of rows is 1 less than the number of chairs in a row and each row has same number of chairs.
Assuming the number of Chairs = C.
Number of rows = C-1
Required: C = ?
Statement 1: Total chairs = 72
Total chairs = (chairs in a row)*(number of rows) = C*(C-1)
C*(C-1) = 72, Hence C =9
SUFFICIENTStatement 2: C + (C-1) =17
Hence C = 9
SUFFICIENTOption D