Subject
Quantitative Aptitude
Topic
Series
The second and third terms of a geometric series are 9 and 3 respectively. The fifth term of the series is -
The second and third terms of a geometric series are 9 and 3 respectively. The fifth term of the series is -
ক)
1খ)
1/9গ)
1/3ঘ)
1/27Explanation
ধরি, ধারাটির প্রথম পদ a এবং এর সাধারণ অনুপাত r = ৩য় পদ/ ২য় পদ =3/9=1/3 এখন, প্রশ্নমতে, ar 2-1 = 9 ⇒ ar=9....................(i) এবং ar 3--1 = 3 ⇒ ar 2 = 3..................(ii) সমীকরণ (ii) কে (i) নং দ্বারা ভাগ করে পাই, ar 2 /ar = 3/9 ∴r= 1/3 r এর মান (i) নং সমীকরণে বসাই, ar=9 ⇒ a*1/3= 9 a=27 অতএব, ধারাটি ৫ম পদটি = ar 5-1 = 27*(1/3) 4 = 27*(1/81) = 1/3Related questions
What is the difference between sixth and fifth terms of the sequence 2,4,7, ___ whose nthterm is n + 2n-1What comes next in this series 3, 8, 15, 24, 35, 48, 63, 80,.......?নিচের ধারাটির পরবর্তী সংখ্যা কত? ১,৪,১৩,৪০,১২১,…..A cube has a volume of 8m3. If each side is doubled in length, what will be its new volume?The numbers 13, 7 and 11 would enjoy the company of which of these numbers: 10, 15, 17, 12, 18?Insert the missing number: 16, 33, 67, 135, 271, (……….).Find the missing number in the following problem. 59 (4) 19, 90 (?) 20, 70 (5) 20Select an appropriate term that completes the serial- L p F, N q G, P r H, R s I,-