+0  
 
0
262
1
avatar

The terms 140, a, \(560\) are the first, second and third terms, respectively, of a geometric sequence. If a is positive, what is the value of a ?

 Jan 30, 2022
 #1
avatar+1224 
0

geometric sequence in general: a, ar, ar^2, ...

where a is the first term and r is the common ratio.

 

140 = a

560 = ar^2

 

Divide to get 4 = r^2, or r = 2. So, the second term is 140 * 2 = 280.

 Jan 30, 2022

1 Online Users