Question

26. The 5th term of a G.P. is 48 and the 12th term is 6144. Find the sum of the
27. In a G.P., the first term is 5, the last term is 320 and the sum is 635. Find
25. Find the least value of n, for which 1 + 3 + 32 +
first 10 terms.
the 4th term.
28. The sum of the first 6 terms of a G.P. is 9 times the sum of the first 3 terms.
If the 7th term be 384, find the sum of the first 10 terms.
29. The sum of the first 10 terms of a G.P. is 33 times the sum of the first 5 terms.
Find the common ratio.
30. The first and the last terms of a G.P. are respectively 3 and 768 and the sum
is 1533. Find the number of terms and the common ratio.
31. If S, S, S, be the sums of the first n terms, 2n terms, 3n terms respectively
of a G.P., prove that
1)
( S.? +S, =S,(S, +S;)
(ii) S(S, -S) =(S+S)
ANSWER
256
97
1. i
(1) 1024 (ii) (i) s262 (iv)
os​

Answer 1

Answer:

1533. Find the number of terms and the common ratio.

31. If S, S, S, be the sums of the first n terms, 2n terms, 3n terms respectively

of a G.P., prove that

1)

( S.? +S, =S,(S, +S;)

(ii) S(S, -S) =(S+S)

ANSWER

256

97

1. i

(1) 1024 (ii) (i) s262 (iv)

os