Answer:

Step-by-step explanation:
We have a geometric sequence with:
,
, and 
Where
Sn is the sum of the sequence
r is the common ratio
is the first term in the sequence
n is the number of terms in the sequence
The formula to calculate the sum of a finite geometric sequence is:

Then:

Now we solve for 


500=4πr^2. first divide 500 from four which will equal 125, then divide 125 with π and it will equal 39.788 . finally √39.788. the answer will be r=6.3 or 6
Step-by-step explanation:
How many ways are there to select 3 candidates from 8 equally qualified recent graduates for
openings in an accounting firm?