CA Foundation Exam  >  CA Foundation Questions  >  The sum of three numbers in G.P. is 70. If th... Start Learning for Free
The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers are
  • a)
    12, 18, 40
  • b)
    10, 20, 40
  • c)
    40, 20, 10
  • d)
    none of these
Correct answer is option 'B,C'. Can you explain this answer?
Most Upvoted Answer
The sum of three numbers in G.P. is 70. If the two extremes by multipl...
Given information:
- Sum of three numbers in G.P. is 70.
- If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP.

Let the three numbers be a, ar and ar^2, where r is the common ratio.

Finding the values of a and r:
a + ar + ar^2 = 70 (sum of three numbers is 70)
a(1 + r + r^2) = 70
a = 70 / (1 + r + r^2)

Using the second condition:
4a * 4ar * 5(ar) is in AP
20ar^3, 80ar^2, 80a are in AP
80ar^2 - 20ar^3 = 80a - 80ar^2
4r(5 - r)(a) = 4(20 - 4r)(a)
r(5 - r) = 5 - r
r^2 - 6r + 5 = 0
(r - 1)(r - 5) = 0
r = 1 or r = 5

If r = 1, then a = 70 / 3, ar = 70 / 3 and ar^2 = 70 / 3
But this is not a valid G.P. as all the terms are equal.

If r = 5, then a = 2, ar = 10 and ar^2 = 50
These are the required numbers in G.P.

Checking the second condition:
4a * 4ar * 5(ar) is in AP
(32, 160, 200) is in AP
160 - 32 = 200 - 160
128 = 40

Therefore, the answer is option B and C (10, 20, 40 and 40, 20, 10).
Free Test
Community Answer
The sum of three numbers in G.P. is 70. If the two extremes by multipl...
Explore Courses for CA Foundation exam
The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer?
Question Description
The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer? for CA Foundation 2024 is part of CA Foundation preparation. The Question and answers have been prepared according to the CA Foundation exam syllabus. Information about The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer? covers all topics & solutions for CA Foundation 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer?.
Solutions for The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer? in English & in Hindi are available as part of our courses for CA Foundation. Download more important topics, notes, lectures and mock test series for CA Foundation Exam by signing up for free.
Here you can find the meaning of The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer?, a detailed solution for The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer? has been provided alongside types of The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice The sum of three numbers in G.P. is 70. If the two extremes by multiplied each by 4 and the mean by 5, the products are in AP. The numbers area)12, 18, 40b)10, 20, 40c)40, 20, 10d)none of theseCorrect answer is option 'B,C'. Can you explain this answer? tests, examples and also practice CA Foundation tests.
Explore Courses for CA Foundation exam

Top Courses for CA Foundation

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev