Discussion
If three geometric means are inserted between 2 and 32, then the three numbers are
Answer: E
The three numbers are 4, 8, 16.
Inserting three geometric means gives a GP of five terms: 2, \(2r\), \(2r^{2}\), \(2r^{3}\), 32.
\[ \begin{aligned} 2r^{4} &= 32 \\ r^{4} &= 16, \quad r = 2 \end{aligned} \]
So the means are 4, 8 and 16, and the sequence 2, 4, 8, 16, 32 doubles at each step. 6, 8, 10 and 4, 6, 8 are arithmetic, not geometric, and 4, 8, 32 repeats the end term instead of reaching it.
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development