Advertisements
Advertisements
Question
The first two terms of a G.P. are 125 and 25 respectively. Find the 5th and the 6th terms of the G.P.
Solution
First term (a) = 125
And common ratio (r) = `25/125 = 1/5`
Now tn = arn – 1
`=>` 5th term = t5
= `125 xx (1/5)^(5 - 1)`
= `125 xx (1/5)^4`
= `125 xx 1/625`
= `1/5`
`=>` 6th term = t6
= `125 xx (1/5)^(6 - 1)`
= `125 xx (1/5)^5`
= `125 xx 1/3125`
= `1/25`
APPEARS IN
RELATED QUESTIONS
Find, which of the following sequence from a G.P. :
8, 24, 72, 216, .............
If the first and the third terms of a G.P. are 2 and 8 respectively, find its second term.
The product of 3rd and 8th terms of a G.P. is 243. If its 4th term is 3, find its 7th term.
Q 5
If a, b and c are in G.P., prove that : log a, log b and log c are in A.P.
Q 2
Find the sum of G.P. :
`(x + y)/(x - y) + 1 + (x - y)/(x + y) + ..........` upto n terms.
How many terms of the geometric progression 1 + 4 + 16 + 64 + …….. must be added to get sum equal to 5461?
Find the geometric mean between `4/9` and `9/4`
Q 3.1