Question on: JAMB Mathematics - 2012
The sum to infinity of a geometric progression is (-\frac{1}{10}) and the first term is (-\frac{1}{8}). Find the common ratio of the progression.
A
\(-\frac{1}{5}\)
B
\(-\frac{1}{4}\)
C
\(-\frac{1}{3}\)
D
\(-\frac{1}{2}\)
Ask EduPadi AI for a detailed answer
Correct Option: B
Sr = (\frac{a}{1 - r})
(-\frac{1}{10}) = (\frac{1}{8} \times \frac{1}{1 - r})
(-\frac{1}{10}) = (\frac{1}{8(1 - r)})
(-\frac{1}{10}) = (\frac{1}{8 - 8r})
cross multiply...
-1(8 - 8r) = -10
-8 + 8r = -10
8r = -2
r = -1/4
Add your answer
Please share this, thanks!
No responses