Find the value of each variable

Afurniture store has 1,500 chairs in storage. a manager uses three delivery receipts to simulate samples to check 100 chairs and note the number of brown chairs. suppose the actual number of brown chairs is 1,080. about how many brown chairs are

Identify a1 and r for the geometric sequence an= -256(-1/4) n-1

Which expression is equivalent to the expression shown?