+0  
 
0
381
1
avatar

An infinite geometric series has common ratio 1/8 and sum 80. What is the first term of the series?

 Jan 6, 2021
 #1
avatar+236 
+1

We can set a to be the first term and r to be the ratio.

Using the infinite geometric series formula \(S=a/(1-r)\) where S is the sum, we can plug in values to get \(80=a/(7/8)\) so a=70.

:D

 Jan 6, 2021

2 Online Users

avatar
avatar